Remove using isdigit since its deprecated

I had put an extra check to see if instance number is a digit
and used POSIX::isdigit for that. However, it's deprecated in
the PERL version that is in the mrw-tools.

Also, no other parsers are doing this explicit check since
the instance number has to be digit and is fundamental and
hence isdigit check is not needed.

Change-Id: I5922e466af6cdd9e9365c1d9ddf54b12a6763a5c
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
diff --git a/gen_occ_map.pl b/gen_occ_map.pl
index 0aba66a..d4eaf25 100755
--- a/gen_occ_map.pl
+++ b/gen_occ_map.pl
@@ -5,7 +5,6 @@
 use mrw::Targets; # Set of APIs allowing access to parsed ServerWiz2 XML output
 use mrw::Inventory; # To get list of Inventory targets
 use Getopt::Long; # For parsing command line arguments
-use POSIX; # For checking if something is a digit
 
 # Globals
 my $force           = 0;
@@ -89,9 +88,6 @@
 
     foreach my $instance (sort keys %occHash)
     {
-        # If the instance is not a digit, then error
-        isdigit($instance) or die "'$instance' does not have instance number";
-
         # YAML with list of {Instance:SensorID} dictionary
         print $fh "- Instance: ";
         print $fh "$instance\n";