fs/befs/linuxvfs.c: remove unnecessary casting

Fix the following coccinelle warning:

  fs/befs/linuxvfs.c:278:14-36: WARNING: casting value returned by memory allocation function to (struct befs_inode_info *) is useless.

[akpm@linux-foundation.org: avoid 80-col ugliness]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>