sysctl: add sanity check for proc_douintvec

Commit e7d316a02f68 ("sysctl: handle error writing UINT_MAX to u32
fields") introduced the proc_douintvec helper function, but it forgot to
add the related sanity check when doing register_sysctl_table.  So add
it now.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Cc: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 8f91ec6..d04ea43 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -1074,6 +1074,7 @@
 
 		if ((table->proc_handler == proc_dostring) ||
 		    (table->proc_handler == proc_dointvec) ||
+		    (table->proc_handler == proc_douintvec) ||
 		    (table->proc_handler == proc_dointvec_minmax) ||
 		    (table->proc_handler == proc_dointvec_jiffies) ||
 		    (table->proc_handler == proc_dointvec_userhz_jiffies) ||