libffi: remove some header files installed in /usr/lib in the target

For some reason, libffi installs some header files in
/usr/lib/libffi-<version>/include, which is a non-standard location
and therefore they do not get removed automatically by the
target-finalize logic. This commit adds a post-install hook in
libffi.mk to get rid of these unneeded headers on the target.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libffi/libffi.mk

@@ -22,6 +22,12 @@ endef
 
 LIBFFI_POST_INSTALL_STAGING_HOOKS += LIBFFI_MOVE_STAGING_HEADERS
 
+# Remove headers that are not at the usual location from the target
+define LIBFFI_REMOVE_TARGET_HEADERS
+	$(RM) -rf $(TARGET_DIR)/usr/lib/libffi-$(LIBFFI_VERSION)
+endef
+
+LIBFFI_POST_INSTALL_TARGET_HOOKS += LIBFFI_REMOVE_TARGET_HEADERS
 
 $(eval $(autotools-package))
 $(eval $(host-autotools-package))