checkpatch: add a fixer for missing newline at eof

Remove the trailing error message from the fixed lines.

Link: https://lkml.kernel.org/r/20201017142546.28988-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -3418,8 +3418,11 @@ sub process {
 
 # check for adding lines without a newline.
 		if ($line =~ /^\+/ && defined $lines[$linenr] && $lines[$linenr] =~ /^\\ No newline at end of file/) {
-			WARN("MISSING_EOF_NEWLINE",
-			     "adding a line without newline at end of file\n" . $herecurr);
+			if (WARN("MISSING_EOF_NEWLINE",
+			         "adding a line without newline at end of file\n" . $herecurr) &&
+			    $fix) {
+				fix_delete_line($fixlinenr+1, "No newline at end of file");
+			}
 		}
 
 # check we are in a valid source file C or perl if not then ignore this hunk