boards: remove duplicate include 'RIOTCPU/cpu/Makefile.features'

[cladmi]

Contribution description

When 'CPU' is defined, the CPU Makefile.features is included by the
build system in the main Makefile.features.
No need to do it manually anymore.

Testing procedure

Compare the output of info-build for all affected boards. Some duplicate includes are now removed:

for board in bluepill blackpill bluepill-128kib blackpill-128kib p-l496g-cell02 samr34-xpro stm32f723e-disco; do BOARD=${board} make --no-print-directory -C examples/hello-world/ info-build | sed "s|${PWD}/||"g ; done

The 3 removed lines in included makefiles in MAKEFILE_LIST are the 3 lines that are already parsed before:

Difference in info-build between master and this PR

--- info-build-master   2019-09-30 12:40:59.110072205 +0200
+++ info-build-pr       2019-09-30 12:40:24.357554378 +0200
@@ -170,9 +170,6 @@
        cpu/stm32f1/Makefile.features  
        cpu/stm32_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/stm32f1/Makefile.features  
-       cpu/stm32_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/bluepill/Makefile.include  
@@ -387,9 +384,6 @@
        cpu/stm32f1/Makefile.features  
        cpu/stm32_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/stm32f1/Makefile.features  
-       cpu/stm32_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/blackpill/Makefile.include  
@@ -604,9 +598,6 @@
        cpu/stm32f1/Makefile.features  
        cpu/stm32_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/stm32f1/Makefile.features  
-       cpu/stm32_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/bluepill-128kib/Makefile.include  
@@ -821,9 +812,6 @@
        cpu/stm32f1/Makefile.features  
        cpu/stm32_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/stm32f1/Makefile.features  
-       cpu/stm32_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/blackpill-128kib/Makefile.include  
@@ -1039,9 +1027,6 @@
        cpu/stm32l4/Makefile.features  
        cpu/stm32_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/stm32l4/Makefile.features  
-       cpu/stm32_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/p-l496g-cell02/Makefile.include  
@@ -1251,9 +1236,6 @@
        cpu/saml21/Makefile.features  
        cpu/sam0_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/saml21/Makefile.features  
-       cpu/sam0_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/samr34-xpro/Makefile.include  
@@ -1466,9 +1448,6 @@
        cpu/stm32f7/Makefile.features  
        cpu/stm32_common/Makefile.features  
        cpu/cortexm_common/Makefile.features  
-       cpu/stm32f7/Makefile.features  
-       cpu/stm32_common/Makefile.features  
-       cpu/cortexm_common/Makefile.features  
        makefiles/pseudomodules.inc.mk  
        makefiles/defaultmodules.inc.mk  
        boards/stm32f723e-disco/Makefile.include  

Issues/PRs references

Part of Tracking: move CPU/CPU_MODEL to Makefile.features #11477

[benpicco]

Makefiles are included automatically, no need for manual includes.

[cladmi]

Thank you for the review, I will rebase the PRs that depended on it.