checkpatch: fix a number of COMPLEX_MACRO false positives

A simple search over the kernel souce displays a number of correctly
defined multiline macro, which generally are used as an array element
initializer:

% find ../linux -type f | xargs grep -B1 -H '^[:space]*\[.*\\$'

However checkpatch.pl unexpectedly complains about all these macro
definitions:

% ./scripts/checkpatch.pl --types COMPLEX_MACRO -f include/linux/perf/arm_pmu.h

ERROR: Macros with complex values should be enclosed in parentheses
+#define PERF_MAP_ALL_UNSUPPORTED					\
+	 [0 ... PERF_COUNT_HW_MAX - 1] = HW_OP_UNSUPPORTED

The change intends to fix this type of false positives by flattening
only array members and skipping array element designators.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkpatch.pl

@@ -4550,7 +4550,7 @@ sub process {
 			# Flatten any parentheses and braces
 			while ($dstat =~ s/\([^\(\)]*\)/1/ ||
 			       $dstat =~ s/\{[^\{\}]*\}/1/ ||
-			       $dstat =~ s/\[[^\[\]]*\]/1/)
+			       $dstat =~ s/.\[[^\[\]]*\]/1/)
 			{
 			}
 
@@ -4570,7 +4570,8 @@ sub process {
 				union|
 				struct|
 				\.$Ident\s*=\s*|
-				^\"|\"$
+				^\"|\"$|
+				^\[
 			}x;
 			#print "REST<$rest> dstat<$dstat> ctx<$ctx>\n";
 			if ($dstat ne '' &&