libcxx: Depenency fixes

Don't build with uClibc-ng. It's totally unsupported as several functions
are missing.

Make the musl libc support conditional.

Fix hash with make check FIXUP=1. Apparently I based the Makefile off of
libedit and forgot to fix the hash.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Fixes: 856ea2bad3 ("libcxx: Add package")

config/Config-build.in

@@ -199,6 +199,7 @@ menu "Global build settings"
 
 		config USE_LIBCXX
 			bool "libc++"
+			depends on !USE_UCLIBC
 
 		config USE_LIBSTDCXX
 			bool "libstdc++"

package/libs/libcxx/Makefile

@@ -7,12 +7,12 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libcxx
 PKG_VERSION:=9.0.1
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL:=https://git.llvm.org/git/libcxx
 PKG_SOURCE_VERSION:=2076f539f410805ef88692b9c0ce0a0b882a7680
-PKG_MIRROR_HASH:=6dff036660d478bfaa14e407fc5de26d22da1087118c897b1a3ad2e90cb7bf39
+PKG_MIRROR_HASH:=d527880a18dec9109575c76717cf5288fb91c11381b9d261cae2e5bebcbdab2e
 
 PKG_MAINTAINER:=Rosen Penev <rosenp@gmail.com>
 PKG_LICENSE:=MIT
@@ -42,8 +42,8 @@ CMAKE_OPTIONS += \
 	-DLIBCXX_INCLUDE_BENCHMARKS=OFF \
 	-DLIBCXX_INCLUDE_DOCS=OFF \
 	-DLIBCXX_INCLUDE_TESTS=OFF \
-	-DLIBCXX_HAS_MUSL_LIBC=ON \
-	-DLIBCXX_STANDALONE_BUILD=ON
+	-DLIBCXX_STANDALONE_BUILD=ON \
+	-DLIBCXX_HAS_MUSL_LIBC=$(if $(CONFIG_USE_MUSL),ON,OFF)
 
 TARGET_CXXFLAGS += -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS -Wno-attributes -flto
 TARGET_LDFLAGS += -Wl,--as-needed