Change in coreboot[master]: lib: Add __fls() (Find Last Set)

[Jianjun Wang (Code Review)]

Attention is currently required from: Hung-Te Lin, Shelley Chen, Paul Menzel, Julius Werner, Yu-Ping Wu.
Jianjun Wang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59738 )

Change subject: lib: Add __fls() (Find Last Set)
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Patch Set 5:

(2 comments)

File src/include/lib.h:

https://review.coreboot.org/c/coreboot/+/59738/comment/985effff_20d7f55a 
PS4, Line 56: /* Find Last Set: fls(1) == 1, fls(0) == 0, fls(1 << 31) == 32 */
> Probably worth mentioning the background in the comment here. […]

Done, thanks for introducing the background.

https://review.coreboot.org/c/coreboot/+/59738/comment/e5bba53f_36a212f1 
PS4, Line 66:
> If you do add anything new here, please also add a 64-bit variant down here and add the equivalents  […]

Done