MFC r317311,r317312,r319019:

r317311:

Check for failures from getpagesize(3)

Return errno on failure, similar to the open(2) call above it.

CID: 1193753

r317312:

Fix type for pagesize to match the return type for getpagesize(3)
to fix the build

Pointyhat to: ngie

r319019:

Remove getpagesize(3) error checking added in r317312

getpagesize(3) no longer fails as of r317436.