intel/compiler: remove abandoned comments

c8665005: ("intel/compiler: Don't always require precise lowering of flrp")
forgot to remove some comments that didn't apply any more after the
change.

Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrnd.net>
10 jobs for !1304 with keep-bit-size-in-flrp in 2 minutes and 1 second (queued for 14 minutes and 24 seconds)
merge request