dev/mfi: Make a seemingly bogus conditional unconditional

dev/mfi: Make a seemingly bogus conditional unconditional

Summary:
r358689 attempted to fix a clang warning/error by inferring the intent
of the condition "(cdb[0] != 0x28 || cdb[0] != 0x2A)".  Unfortunately, it looks
like this broke things.  Instead, fix this by making this path unconditional,
effectively reverting to the previous state.

PR:		kern/251483
Reviewed By:	ambrisko
MFC after:	2 days
Differential Revision: https://reviews.freebsd.org/D27515