changed so the linkerscript is passed through the preprocessor #420

Job	Run time
Build each header individually	13s
build (max32660)	12s
build (lpc1788)	13s
build (max32625)	14s
build (rp2350)	12s
build (atsam4s2b)	11s
build (lpc55s66)	13s
build (lpc1759)	11s
build (stm32f407)	11s
build (lpc1754)	12s
build (mb9bf566k)	14s
build (atsam3x8e)	11s
build (lpc1756)	13s
build (stm32h723)	15s
build (lpc802)	12s
build (tmpm373)	12s
build (stm32f103)	14s
build (lpc1752)	13s
	3m 46s

Provide feedback