target/ppc: Deprecate Power8E and Power8NVL

Power8E and Power8NVL variants are not of much use in QEMU now, and not
being maintained either.

Power8NVL CPU doesn't boot since skiboot v7.0, or following skiboot commit
to be exact:

    commit c5424f683ee3 ("Remove support for POWER8 DD1")

Deprecate the 8E and 8NVL variants.

Suggested-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Aditya Gupta <adityag@linux.ibm.com>
Tested-by: Anushree Mathur <anushree.mathur@linux.ibm.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Link: https://lore.kernel.org/r/20250607110412.2342511-3-adityag@linux.ibm.com
Message-ID: <20250607110412.2342511-3-adityag@linux.ibm.com>

Author: adi-g15-ibm

docs/about/deprecated.rst

@@ -253,6 +253,15 @@ embedded 405 for power management (OCC) and other internal tasks, it
 is theoretically possible to use QEMU to model them. Let's keep the
 CPU implementation for a while before removing all support.
 
+Power8E and Power8NVL CPUs and corresponding Pnv chips (since 10.1)
+'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+The Power8E and Power8NVL variants of Power8 are not really useful anymore
+in qemu, and are old and unmaintained now.
+
+The CPUs as well as corresponding Power8NVL and Power8E PnvChips will also
+be considered deprecated.
+
 System emulator machines
 ------------------------
 

target/ppc/cpu-models.c

@@ -739,12 +739,12 @@
                 "POWER7 v2.3")
     POWERPC_DEF("power7p_v2.1",  CPU_POWERPC_POWER7P_v21,            POWER7,
                 "POWER7+ v2.1")
-    POWERPC_DEF("power8e_v2.1",  CPU_POWERPC_POWER8E_v21,            POWER8,
-                "POWER8E v2.1")
+    POWERPC_DEPRECATED_CPU("power8e_v2.1",  CPU_POWERPC_POWER8E_v21, POWER8,
+                "POWER8E v2.1", "CPU is unmaintained.")
     POWERPC_DEF("power8_v2.0",   CPU_POWERPC_POWER8_v20,             POWER8,
                 "POWER8 v2.0")
-    POWERPC_DEF("power8nvl_v1.0", CPU_POWERPC_POWER8NVL_v10,         POWER8,
-                "POWER8NVL v1.0")
+    POWERPC_DEPRECATED_CPU("power8nvl_v1.0", CPU_POWERPC_POWER8NVL_v10, POWER8,
+                "POWER8NVL v1.0", "CPU is unmaintained.")
     POWERPC_DEF("power9_v2.0",   CPU_POWERPC_POWER9_DD20,            POWER9,
                 "POWER9 v2.0")
     POWERPC_DEF("power9_v2.2",   CPU_POWERPC_POWER9_DD22,            POWER9,