uclibc++: remove

No package here depends on it. Furthermore, uClibc++ is a fairly buggy
C++ library and seems to be relatively inactive upstream.

It also lacks proper support for modern C++11 features.

The main benefit of it is size: 66.6 KB	vs 287.3 KB on mips24kc. Static
linking and LTO can help bring the size down of packages that need it.

Added warning message to uclibc++.mk

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>

config/Config-build.in

@@ -217,20 +217,6 @@ menu "Global build settings"
 		  make the system libraries incompatible with most of the packages that are
 		  not selected during the build process.
 
-	choice
-		prompt "Preferred standard C++ library"
-		default USE_LIBSTDCXX if USE_GLIBC
-		default USE_UCLIBCXX
-		help
-		  Select the preferred standard C++ library for all packages that support this.
-
-		config USE_UCLIBCXX
-			bool "uClibc++"
-
-		config USE_LIBSTDCXX
-			bool "libstdc++"
-	endchoice
-
 	comment "Hardening build options"
 
 	config PKG_CHECK_FORMAT_SECURITY

include/uclibc++.mk

@@ -1,16 +1,2 @@
-ifndef DUMP
-  ifdef __package_mk
-    $(error uclibc++.mk must be included before package.mk)
-  endif
-endif
-
-PKG_PREPARED_DEPENDS += CONFIG_USE_UCLIBCXX
-CXX_DEPENDS = +USE_UCLIBCXX:uclibcxx +USE_LIBSTDCXX:libstdcpp
-
-ifneq ($(CONFIG_USE_UCLIBCXX),)
- ifneq ($(CONFIG_CCACHE),)
-  TARGET_CXX_NOCACHE=g++-uc
- else
-  TARGET_CXX=g++-uc
- endif
-endif
+$(warn uclibc++.mk is deprecated. Please remove it and CXX_DEPENDS)
+CXX_DEPENDS = +libstdcpp