cleanup: Ignoring libwally artifacts and distclean cleans them

.gitignore

@@ -13,8 +13,8 @@ libsecp256k1.a
 libsecp256k1.la
 libsodium.a
 libsodium.la
-libwally-core.a
+libwallycore.a
-libwally-core.la
+libwallycore.la
 gen_*
 daemon/lightning-cli
 check-bolt

Makefile

@@ -357,6 +357,7 @@ distclean: clean
 	$(MAKE) -C secp256k1/ distclean || true
 	$(RM) libsecp256k1.a secp256k1/libsecp256k1.la
 	$(RM) libsodium.a libsodium/libsodium.la
+	$(RM) libwallycore.a libwallycore.la
 	cd libwally-core && tools/cleanup.sh
 
 maintainer-clean: distclean