Disabling HCC code object v3 generation by default.

Some PyTorch unit tests have regression.  Disabling cov3 to allow more
time to debug and unblock PyTorch

Change-Id: Iba7f425ef3499c20c42ec45d9152b5d27ce97d03


[ROCm/hip commit: f2ab87d872]

projects/hip/bin/hipcc

@@ -342,7 +342,7 @@ my $runCmd = 1;
 my $buildDeps = 0;
 my $linkType = 1;
 my $setLinkType = 0;
-my $coFormatv3 = 1;
+my $coFormatv3 = 0;
 
 my @options = ();
 my @inputs  = ();