checkpatch: improve CONSTANT_COMPARISON test for structure members

A "." dereference to an all uppercase structure member can be
incorrectly reported as a CONSTANT_COMPARISON.

ie: "if (table[i].PANELID == tempdx)"

Fix it by checking for "." before the constant test.

Signed-off-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

@@ -4291,7 +4291,7 @@ sub process {
 			my $comp = $3;
 			my $to = $4;
 			my $newcomp = $comp;
-			if ($lead !~ /$Operators\s*$/ &&
+			if ($lead !~ /(?:$Operators|\.)\s*$/ &&
 			    $to !~ /^(?:Constant|[A-Z_][A-Z0-9_]*)$/ &&
 			    WARN("CONSTANT_COMPARISON",
 				 "Comparisons should place the constant on the right side of the test\n" . $herecurr) &&