perl: fixed host compilation of static perl on MacOS

All symbols on MacOS are prefixed with an underscore which
interfered with the filtering mechanism (added in perl 5.28)
for extension libraries to be linked into static perl.

Signed-off-by: Jakub Piotr Cłapa <jpc@loee.pl>

lang/perl/Makefile

@@ -11,7 +11,7 @@ include perlver.mk
 
 PKG_NAME:=perl
 PKG_VERSION:=$(PERL_VERSION)
-PKG_RELEASE:=2
+PKG_RELEASE:=3
 
 PKG_SOURCE_URL:=\
 		https://cpan.metacpan.org/src/5.0 \

lang/perl/patches/301-fix_macos_static_linking.patch

@@ -0,0 +1,19 @@
+--- a/cpan/ExtUtils-MakeMaker/lib/ExtUtils/MM_Unix.pm
++++ b/cpan/ExtUtils-MakeMaker/lib/ExtUtils/MM_Unix.pm
+@@ -2738,14 +2738,14 @@ sub _find_static_libs {
+ 
+ Called by a utility method of makeaperl. Checks whether a given file
+ is an XS library by seeing whether it defines any symbols starting
+-with C<boot_>.
++with C<boot_> (with an optional leading underscore – needed on MacOS).
+ 
+ =cut
+ 
+ sub xs_static_lib_is_xs {
+     my ($self, $libfile) = @_;
+     my $devnull = File::Spec->devnull;
+-    return `nm $libfile 2>$devnull` =~ /\bboot_/;
++    return `nm $libfile 2>$devnull` =~ /\b_?boot_/;
+ }
+ 
+ =item makefile (o)