gcc-core:

- add LTO support
- disable build of libada
- disable __cxa_atexit

packages/toolchain/lang/gcc-core/build

@@ -30,6 +30,9 @@ LDFLAGS="-Wl,-rpath,$ROOT/$TOOLCHAIN/lib" \
              --with-cloog=$ROOT/$TOOLCHAIN \
              --with-libelf=$ROOT/$TOOLCHAIN \
              --enable-languages=c \
+             --disable-__cxa_atexit \
+             --enable-lto \
+             --disable-libada \
              --disable-libmudflap \
              --disable-libssp \
              --disable-libgomp \