cpu/x86/mtrr/earlymtrr: Validate MTRR arguments

cpu/x86/mtrr/earlymtrr: Validate MTRR arguments

The AMD64 Architecture Programmer's Manual, Volume 2: Systems
Programming says the following about variable MTRRs:

Variable Range Size and Alignment.
The size and alignment of variable memory-ranges (MTRRs) and I/O ranges
(IORRs) are restricted as follows:
* The boundary on which a variable range is aligned must be equal to the
range size. For example, a memory range of 16 Mbytes must be aligned on a
16-Mbyte boundary (i.e., naturally aligned).
* The range size must be a power of 2 (2^n , 52 > n > 11), with a minimum
allowable size of 4 Kbytes. For example, 4 Mbytes and 8 Mbytes are
allowable memory range sizes, but 6 Mbytes is not allowable.

Print out errors if these conditions are violated. I didn't assert since
`set_var_mtrr` can be used in boot block before the serial console is
enabled.

BUG=b:147042464
TEST=Boot trembyle and see MTRR errors:
MTRR Error: base 0xcc800000 must be aligned to size 0x1000000

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I8b8c734c7599bd89cf9f212ed43c2dd5b2c8ba7b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40762
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>