ext4: rename {ext,idx}_pblock and inline small extent functions

Cleanup namespace leaks from fs/ext4 and the inline trivial functions
ext4_{ext,idx}_pblock() and ext4_{ext,idx}_store_pblock() since the
code size actually shrinks when we make these functions inline,
they're so trivial.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --cc fs/ext4/ext4_extents.h
Simple merge

diff --cc fs/ext4/extents.c
Simple merge

diff --cc fs/ext4/migrate.c
Simple merge

diff --cc fs/ext4/move_extent.c
Simple merge