corrected path to hipgenisa.sh and fixed its working

Change-Id: I140055d5e800cd4b23253171ba889db5e63b637b

bin/hipcc

@@ -157,7 +157,8 @@ if ($HIP_PLATFORM eq "hcc") {
     exit (-1);
 }
 
-my $ISACMD="hipgenisa.sh ";
+my $ISACMD=$HIP_PATH;
+$ISACMD .= "/bin/hipgenisa.sh ";
 $ISACMD .= $ROCM_PATH;
 if($ARGV[0] eq "--genisa"){
   foreach $isaarg (@ARGV){