x86/spectre: move microcode check before kernel ibrs flags are set

x86/spectre: move microcode check before kernel ibrs flags are set

The check for bad spectre microcode, which prints "disabling
SPEC_CTRL/IBRS", happens after the kernel turns on its flags for "IBRS
supported" and "IBRS in use"

When the microcode check runs, it disables the CPU capability but the
kernel flags have already been set based on the disabled capability.

So to fix it, we should move the microcode check to before the kernel
flags are set.

Orabug: 27542331
CVE: CVE-2017-5715
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>