initialized some values in 'fs' and 'system' graphs to avoid error messages on BSD systems

Changes

@@ -1,3 +1,11 @@
+3.N.N  - NN-XXX-2013
+====================
+- Fixed error messages about use of uninitialized values in 'system' graph on
+  BSD systems.
+- Fixed error messages about not numeric argument in addition in 'fs' graph on
+  BSD systems.
+
+
 3.3.1  - 21-Nov-2013
 ====================
 - Fixed to correctly sanitize the input string in the built-in HTTP server

lib/fs.pm

@@ -455,8 +455,8 @@ sub fs_update {
 				} elsif($config->{os} eq "OpenBSD" || $config->{os} eq "NetBSD") {
 					@tmp = split(' ', `iostat -DI | tail -1`);
 					($read_cnt, $read_sec) = @tmp;
-					$write_cnt = "";
-					$write_sec = "";
+					$write_cnt = 0;
+					$write_sec = 0;
 					chomp($read_sec);
 					$read_sec = int($read_sec);
 				}

lib/system.pm

@@ -108,22 +108,22 @@ sub system_update {
 	my $rrd = $config->{base_lib} . $package . ".rrd";
 	my $system = $config->{system};
 
-	my $load1;
-	my $load5;
-	my $load15;
-	my $nproc;
-	my $npslp;
-	my $nprun;
-	my $npwio;
-	my $npzom;
-	my $npstp;
-	my $npswp;
-	my $mtotl;
-	my $mbuff;
-	my $mcach;
-	my $mfree;
-	my $macti;
-	my $minac;
+	my $load1 = 0;
+	my $load5 = 0;
+	my $load15 = 0;
+	my $nproc = 0;
+	my $npslp = 0;
+	my $nprun = 0;
+	my $npwio = 0;
+	my $npzom = 0;
+	my $npstp = 0;
+	my $npswp = 0;
+	my $mtotl = 0;
+	my $mbuff = 0;
+	my $mcach = 0;
+	my $mfree = 0;
+	my $macti = 0;
+	my $minac = 0;
 	my $val01 = 0;
 	my $val02 = 0;
 	my $val03 = 0;