Change in coreboot[master]: src: use ARRAY_SIZE where possible

[Angel Pons (Code Review)]

Attention is currently required from: Patrick Rudolph, HAOUAS Elyes.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50594 )

Change subject: src: use ARRAY_SIZE where possible
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Patch Set 2: Code-Review+2

(2 comments)

File src/arch/x86/cpu.c:

https://review.coreboot.org/c/coreboot/+/50594/comment/7c19ea2f_54b4f901 
PS2, Line 126: ARRAY_SIZE
> It's pretty universally available through stddef.h. […]

Or just include types.h

File src/vendorcode/cavium/bdk/libbdk-dram/bdk-dram-test.c:

https://review.coreboot.org/c/coreboot/+/50594/comment/fb1b666f_1de5f299 
PS2, Line 135: int
for another patch: make this unsigned and drop the cast