mm/hugetlb.c: replace memfmt with string_get_size

mm/hugetlb.c: replace memfmt with string_get_size

The hugetlb code has its own function to report human-readable sizes.
Convert it to use the shared string_get_size() function.  This will lead
to a minor difference in user visible output (MiB/GiB instead of MB/GB),
but some would argue that's desirable anyway.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Matthew Wilcox <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: Aneesh Kumar K.V <[email protected]>
Cc: Gerald Schaefer <[email protected]>
Cc: zhong jiang <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>