x86, microcode, AMD: Extend ucode size verification

x86, microcode, AMD: Extend ucode size verification

commit 44d60c0f5c58c2168f31df9a481761451840eb54 upstream.

The different families have a different max size for the ucode patch,
adjust size checking to the family we're running on. Also, do not
vzalloc the max size of the ucode but only the actual size that is
passed on from the firmware loader.

[PG: baseline of 44d60c0f5~1 differs in multiple trivial ways from
 the 34's; this commit makes get_next_ucode() look like 44d60c0f5's]

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>