perl-gd: fix build of native part

EUMM don't find .xs file in subdirectory (only .pm files are handled)
So, let move lib/GD.xs in the root directory.

Signed-off-by: Francois Perrad <francois.perrad@gadz.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/perl-gd/perl-gd.mk

@@ -12,6 +12,11 @@ PERL_GD_LICENSE = Artistic or GPLv1+
 PERL_GD_LICENSE_FILES = LICENSE
 PERL_GD_PREFER_INSTALLER = EUMM
 
+define PERL_GD_MOVE_XS
+	mv $(@D)/lib/GD.xs $(@D)/GD.xs
+endef
+PERL_GD_POST_PATCH_HOOKS += PERL_GD_MOVE_XS
+
 PERL_GD_CONF_OPTS = \
 	-options=FT,PNG \
 	-lib_gd_path=$(STAGING_DIR)/usr \