libstdc++ is part of gcc, use the version from gcc

package/libstdcxx/Makefile

@@ -2,16 +2,7 @@
 # material, please see the LICENCE file in the top-level directory.
 
 include ${ADK_TOPDIR}/rules.mk
-
-ifeq ($(ADK_TARGET_LIB_GLIBC),y)
-include ${ADK_TOPDIR}/toolchain/glibc/Makefile.inc
-endif
-ifeq ($(ADK_TARGET_LIB_MUSL),y)
-include ${ADK_TOPDIR}/toolchain/musl/Makefile.inc
-endif
-ifeq ($(ADK_TARGET_LIB_UCLIBC_NG),y)
-include ${ADK_TOPDIR}/toolchain/uclibc-ng/Makefile.inc
-endif
+include ${ADK_TOPDIR}/toolchain/gcc/Makefile.inc
 
 PKG_NAME:=		libstdcxx
 PKG_DESCR:=		c++ support library
@@ -31,6 +22,6 @@ do-install:
 	${INSTALL_DIR} ${IDIR_LIBSTDCXX}/usr/${ADK_TARGET_LIBC_PATH}
 	$(CP) ${STAGING_TARGET_DIR}/usr/${ADK_TARGET_LIBC_PATH}/libstdc++.so* \
 		${IDIR_LIBSTDCXX}/usr/${ADK_TARGET_LIBC_PATH}
-	-@rm ${IDIR_LIBSTDCXX}/usr/${ADK_TARGET_LIBC_PATH}/libstdc++.so.*-gdb.py
+	-@rm ${IDIR_LIBSTDCXX}/usr/${ADK_TARGET_LIBC_PATH}/libstdc++.so.*-gdb.py 2>/dev/null
 
 include ${ADK_TOPDIR}/mk/pkg-bottom.mk