size_t in cma_alloc is confusing since it makes people think it's byte
count, not pages.  Change it to unsigned long[1].

The unsigned int in cma_release is also not right so change it.  Since we
have unsigned long in cma_release, free_contig_range should also respect
it.

[1] 67a2e213, mm: cma: fix incorrect type conversion for size during dma allocation

Link: https://lore.kernel.org/linux-mm/20210324043434.GP1719932@casper.infradead.org/
Link: https://lkml.kernel.org/r/20210331164018.710560-1-minchan@kernel.orgSigned-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>