x86: Expanding test-memmove.c, test-memcpy.c, bench-memcpy-large.c

No Bug. This commit expanding the range of tests / benchmarks for
memmove and memcpy. The test expansion is mostly in the vein of
increasing the maximum size, increasing the number of unique
alignments tested, and testing both source < destination and vice
versa. The benchmark expansaion is just to increase the number of
unique alignments. test-memcpy, test-memccpy, test-mempcpy,
test-memmove, and tst-memmove-overflow all pass.

Signed-off-by: Noah Goldstein <goldstein.w.n@gmail.com>