qnx4: get rid of qnx4_bread/qnx4_getblk

pointless, since the only caller will want the physical block
number anyway; might as well call qnx4_block_map() and use
sb_bread()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --cc fs/qnx4/inode.c
Simple merge

diff --cc fs/qnx4/namei.c
Simple merge

diff --cc fs/qnx4/qnx4.h
Simple merge