chainlint.pl: fix incorrect CPU count on Linux SPARC

On SPARC systems running Linux, individual processors are denoted with
"CPUnn:" in /proc/cpuinfo instead of the usual "processor : NN". As a
result, the regexp in ncores() matches 0 times. Address this shortcoming
by extending the regexp to also match lines with "CPUnn:".

Signed-off-by: John Paul Adrian Glaubitz <[email protected]>
[es: simplified regexp; tweaked commit message]
Signed-off-by: Eric Sunshine <[email protected]>
Tested-by: John Paul Adrian Glaubitz  <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: glaubitz

t/chainlint.pl

@@ -715,7 +715,7 @@ sub ncores {
 	if (open my $fh, '<', '/proc/cpuinfo') {
 		my $cpuinfo = do { local $/; <$fh> };
 		close($fh);
-		my @matches = ($cpuinfo =~ /^processor[\s\d]*:/mg);
+		my @matches = ($cpuinfo =~ /^(processor|CPU)[\s\d]*:/mg);
 		return @matches ? scalar(@matches) : 1;
 	}
 	# macOS & BSD