mpc85xx: add support for cpu type 8548

8540 cpu type corresponds to e500v1 core while
8548 cpu type corresponds to e500v2 core

See https://www.nxp.com/products/processors-and-microcontrollers/legacy-mpu-mcus/powerquicc-processors:POWERQUICC_HOME#powerquicc-iii-mpc85xx
and https://www.nxp.com/docs/en/application-note/AN2807.pdf .

Co-authored-by: Josef Schlehofer <[email protected]>
Co-authored-by: Pali Rohár <[email protected]>
Signed-off-by: Šimon Bořek <[email protected]>

include/target.mk

@@ -235,6 +235,7 @@ ifeq ($(DUMP),1)
   ifeq ($(ARCH),powerpc)
     CPU_CFLAGS_603e:=-mcpu=603e
     CPU_CFLAGS_8540:=-mcpu=8540
+    CPU_CFLAGS_8548:=-mcpu=8548
     CPU_CFLAGS_405:=-mcpu=405
     CPU_CFLAGS_440:=-mcpu=440
     CPU_CFLAGS_464fp:=-mcpu=464fp