x86/microcode/AMD: Use native_cpuid() in load_ucode_amd_bsp()

When CONFIG_PARAVIRT is selected, cpuid() becomes a call. Since
for 32-bit kernels load_ucode_amd_bsp() is executed before paging
is enabled the call cannot be completed (as kernel virtual addresses
are not reachable yet).

Use native_cpuid() instead which is an asm wrapper for the CPUID
instruction.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jürgen Gross <jgross@suse.com>
Link: http://lkml.kernel.org/r/1481906392-3847-1-git-send-email-boris.ostrovsky@oracle.com
Link: http://lkml.kernel.org/r/20161218164414.9649-5-bp@alien8.de


Signed-off-by: Thomas Gleixner <tglx@linutronix.de>