checkversion: perl cleanup

Turn on strict checking.
Use three arguement open
Standard practice in perl is to use undef not zero for false

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Cong Wang <amwang@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>

scripts/checkversion.pl

@@ -5,23 +5,22 @@
 # including <linux/version.h> that don't need it.
 # Copyright (C) 2003, Randy Dunlap <rdunlap@xenotime.net>
 
+use strict;
+
 $| = 1;
 
-my $debugging = 0;
+my $debugging;
 
-foreach $file (@ARGV)
-{
+foreach my $file (@ARGV) {
     # Open this file.
-    open(FILE, $file) || die "Can't open $file: $!\n";
+    open( my $f, '<', $file )
+      or die "Can't open $file: $!\n";
 
     # Initialize variables.
-    my $fInComment   = 0;
-    my $fInString    = 0;
-    my $fUseVersion   = 0;
+    my ($fInComment, $fInString, $fUseVersion);
     my $iLinuxVersion = 0;
 
-    LINE: while ( <FILE> )
-    {
+    while (<$f>) {
 	# Strip comments.
 	$fInComment && (s+^.*?\*/+ +o ? ($fInComment = 0) : next);
 	m+/\*+o && (s+/\*.*?\*/+ +go, (s+/\*.*$+ +o && ($fInComment = 1)));
@@ -43,8 +42,8 @@
 	# Look for uses: LINUX_VERSION_CODE, KERNEL_VERSION, UTS_RELEASE
 	if (($_ =~ /LINUX_VERSION_CODE/) || ($_ =~ /\WKERNEL_VERSION/)) {
 	    $fUseVersion = 1;
-	    last LINE if $iLinuxVersion;
-	}
+            last if $iLinuxVersion;
+        }
     }
 
     # Report used version IDs without include?
@@ -67,5 +66,5 @@
         }
     }
 
-    close(FILE);
+    close($f);
 }