tests: skip framework recasting if CMake unavailable

test cases/osx/9 framework recasting/meson.build

@@ -1,5 +1,9 @@
 project('framework recasting', 'c', 'cpp')
 
+if not find_program('cmake', required: false).found()
+  error('MESON_SKIP_TEST cmake binary not available.')
+endif
+
 x = dependency('OpenAL', method: 'cmake')
 
 y = executable('tt', files('main.cpp'), dependencies: x)