Drop pkg-config for static libs

[ljbade]

For all the statically linked libs we should stop using pkg-config becuase most libraries do not provide a valid .pc file for static linking.

See http://stackoverflow.com/questions/27586503/how-to-use-pkg-config-to-link-a-library-statically

Currently I am seeing link commnads with a mix of static and dynamic link flags for the same library. This is just asking for trouble, no to mention a missing symbol will result in a run-time error instead of a compile time error - I have hit this many times on Android.

@kkaefer Said pkg-config is needed for GLFW, so assuming they maintain a valid .pc we can leave that lib alone.

[springmeyer]

I'm on board with reducing dependence on pkg-config wherever possible (#12). But GLFW is certainly a case we should keep pkg-config around for.

[kkaefer]

An example of a package that seems broken is curl and openssl:

'openssl_static_libs%': ['/Users/kkaefer/Code/gl/native/mason_packages/android-arm-v5-9/openssl/1.0.1l/lib/libssl.a'],
'openssl_cflags%': ['-I/Users/kkaefer/Code/gl/native/mason_packages/android-arm-v5-9/openssl/1.0.1l/include'],
'openssl_ldflags%': ['-L/Users/kkaefer/Code/gl/native/mason_packages/android-arm-v5-9/openssl/1.0.1l/lib', '-lssl', '-lcrypto', '-ldl'],
'curl_static_libs%': ['/Users/kkaefer/Code/gl/native/mason_packages/android-arm-v5-9/libcurl/7.40.0/lib/libcurl.a'],
'curl_cflags%': ['-DCURL_STATICLIB', '-I/Users/kkaefer/Code/gl/native/mason_packages/android-arm-v5-9/libcurl/7.40.0/include'],
'curl_ldflags%': ['-L/Users/kkaefer/Code/gl/native/mason_packages/android-arm-v5-9/libcurl/7.40.0/lib', '-lcurl', '-lssl', '-lcrypto', '-lssl', '-lcrypto', '-lz'],

You'll see that the ldflags contain other libs as well, even though they should be folded into the static archives.

[springmeyer]

Closing. The motivation for this ticket was solved by using mason.cmake to avoid a runtime dependency on pkg-config after mapbox/mapbox-gl-native#5359

[kkaefer]

In particular, this is solved by including a mason.ini file in packages to avoid calling the original packages build system in #176