__deprecated not supported on clang.

[lhunath]

Cannot compile json-c for Android under clang, this appears related to #370.

  FAILED: /Users/lhunath/Library/Android/sdk/ndk-bundle/toolchains/llvm/prebuilt/darwin-x86_64/bin/clang  --target=x86_64-none-linux-android --gcc-toolchain=/Users/lhunath/Library/Android/sdk/ndk-bundle/toolchains/x86_64-4.9/prebuilt/darwin-x86_64 --sysroot=/Users/lhunath/Library/Android/sdk/ndk-bundle/sysroot -DMPW_JSON=1 -DMPW_SODIUM=1 -Dmpw_EXPORTS -I"../../../../../lib/libsodium/build-android~/out" -I"../../../../../lib/libjson-c/build-android~/out" -isystem /Users/lhunath/Library/Android/sdk/ndk-bundle/sysroot/usr/include/x86_64-linux-android -D__ANDROID_API__=21 -g -DANDROID -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -Wa,--noexecstack -Wformat -Werror=format-security  -O0 -fno-limit-debug-info  -fPIC -MD -MT CMakeFiles/mpw.dir/Users/lhunath/Documents/workspace/lyndir/MasterPassword/platform-independent/c/core/src/mpw-marshal-util.c.o -MF CMakeFiles/mpw.dir/Users/lhunath/Documents/workspace/lyndir/MasterPassword/platform-independent/c/core/src/mpw-marshal-util.c.o.d -o CMakeFiles/mpw.dir/Users/lhunath/Documents/workspace/lyndir/MasterPassword/platform-independent/c/core/src/mpw-marshal-util.c.o   -c /Users/lhunath/Documents/workspace/lyndir/MasterPassword/platform-independent/c/core/src/mpw-marshal-util.c
  In file included from /Users/lhunath/Documents/workspace/lyndir/MasterPassword/platform-independent/c/core/src/mpw-marshal-util.c:21:
  In file included from /Users/lhunath/Documents/workspace/lyndir/MasterPassword/platform-independent/c/core/src/mpw-marshal-util.h:24:
  In file included from ../../../../../lib/libjson-c/build-android~/out/json-c/json.h:21:
  In file included from ../../../../../lib/libjson-c/build-android~/out/json-c/linkhash.h:16:
  ../../../../../lib/libjson-c/build-android~/out/json-c/json_object.h:429:26: error: expected function body after function declarator
                                                    const char *key) __deprecated;
                                                                     ^

[lhunath]

Going to close this until I have a better idea on whether this issue is relevant or an artifact of local changes.