hugetlbfs: remove unneeded header file

The header file signal.h is unneeded now. Remove it.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Miaohe Lin <[email protected]>
Reviewed-by: Mike Kravetz <[email protected]>
Reviewed-by: Muchun Song <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: MiaoheLin

fs/hugetlbfs/inode.c

@@ -11,7 +11,6 @@
 
 #include <linux/thread_info.h>
 #include <asm/current.h>
-#include <linux/sched/signal.h>		/* remove ASAP */
 #include <linux/falloc.h>
 #include <linux/fs.h>
 #include <linux/mount.h>