[PATCH v2] lib/build_OID_registry: Avoid non-destructive substitution for Perl < 5.13.2 compat

[Paul Menzel]

On a system with Perl 5.12.1, commit 5ef6dc08cfde
("lib/build_OID_registry: don't mention the full path of the script in
output") causes the build to fail with the error below.

     Bareword found where operator expected at ./lib/build_OID_registry line 41, near "s#^\Q$abs_srctree/\E##r"
     syntax error at ./lib/build_OID_registry line 41, near "s#^\Q$abs_srctree/\E##r"
     Execution of ./lib/build_OID_registry aborted due to compilation errors.
     make[3]: *** [lib/Makefile:352: lib/oid_registry_data.c] Error 255

Ahmad Fatoum analyzed that non-destructive substitution is only supported since
Perl 5.13.2. Instead of dropping `r` and having the side effect of modifying
`$0`, introduce a dedicated variable to support older Perl versions.

Fixes: 5ef6dc08cfde ("lib/build_OID_registry: don't mention the full path of the script in output")
Link: https://lore.kernel.org/all/259f7a87-2692-480e-9073-1c1c35b52f67@xxxxxxxxxxxxx/
Solution-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
Cc: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Cc: Nicolas Schier <nicolas@xxxxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: kernel@xxxxxxxxxxxxxx
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
Cc: it+linux-kconfig@xxxxxxxxxxxxx
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
---
v2: Do not split Fixes tags over more than one line.

 lib/build_OID_registry | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/build_OID_registry b/lib/build_OID_registry
index 56d8bafeb848b..8267e8d71338b 100755
--- a/lib/build_OID_registry
+++ b/lib/build_OID_registry
@@ -38,7 +38,9 @@ close IN_FILE || die;
 #
 open C_FILE, ">$ARGV[1]" or die;
 print C_FILE "/*\n";
-print C_FILE " * Automatically generated by ", $0 =~ s#^\Q$abs_srctree/\E##r, ".  Do not edit\n";
+my $scriptname = $0;
+$scriptname =~ s#^\Q$abs_srctree/\E##;
+print C_FILE " * Automatically generated by ", $scriptname, ".  Do not edit\n";
 print C_FILE " */\n";
 
 #
-- 
2.40.1