chainlint.pl: fix /proc/cpuinfo regexp

29fb2ec (chainlint.pl: validate test scripts in parallel,
2022-09-01) introduced a function that gets the number of cores from
/proc/cpuinfo on some systems, notably linux.

The regexp it uses (^processor\s*:) fails to match the desired lines in
the s390x architecture, where they look like this:

    processor 0: version = FF, identification = 148F67, machine = 2964

As a result, on s390x that function returns 0 as the number of cores,
and the chainlint.pl script exits without doing anything.

Signed-off-by: Andreas Hasenack <[email protected]>
Acked-by: Eric Sunshine <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: panlinux

t/chainlint.pl

@@ -656,7 +656,7 @@ sub ncores {
 	# Windows
 	return $ENV{NUMBER_OF_PROCESSORS} if exists($ENV{NUMBER_OF_PROCESSORS});
 	# Linux / MSYS2 / Cygwin / WSL
-	do { local @ARGV='/proc/cpuinfo'; return scalar(grep(/^processor\s*:/, <>)); } if -r '/proc/cpuinfo';
+	do { local @ARGV='/proc/cpuinfo'; return scalar(grep(/^processor[\s\d]*:/, <>)); } if -r '/proc/cpuinfo';
 	# macOS & BSD
 	return qx/sysctl -n hw.ncpu/ if $^O =~ /(?:^darwin$|bsd)/;
 	return 1;