scripts/checkpatch.pl: __GFP_NOFAIL isn't going away

Revert commit 7e4915e78992 ("checkpatch: add warning of future
__GFP_NOFAIL use").

There are no plans to remove __GFP_NOFAIL.

__GFP_NOFAIL exists to

a) centralise the retry-allocation-for-ever operation into the core
   allocator, which is the appropriate implementation site and

b) permit us to identify code sites which aren't handling memory
   exhaustion appropriately.

Cc: David Rientjes <rientjes@google.com>
Cc: Joe Perches <joe@perches.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 33072d6c..d9b09eb 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4330,12 +4330,6 @@
 			     "$1 uses number as first arg, sizeof is generally wrong\n" . $herecurr);
 		}
 
-# check for GFP_NOWAIT use
-		if ($line =~ /\b__GFP_NOFAIL\b/) {
-			WARN("__GFP_NOFAIL",
-			     "Use of __GFP_NOFAIL is deprecated, no new users should be added\n" . $herecurr);
-		}
-
 # check for multiple semicolons
 		if ($line =~ /;\s*;\s*$/) {
 			if (WARN("ONE_SEMICOLON",