backend/ninja: pass language name instead of compiler

Traceback (most recent call last):
  File "F:\avian\meson\mesonbuild\mesonmain.py", line 289, in run
    app.generate()
  File "F:\avian\meson\mesonbuild\mesonmain.py", line 179, in generate
    g.generate(intr)
  File "F:\avian\meson\mesonbuild\backend\ninjabackend.py", line 185, in generate
    self.generate_rules(outfile)
  File "F:\avian\meson\mesonbuild\backend\ninjabackend.py", line 745, in generate_rules
    self.generate_compile_rules(outfile)
  File "F:\avian\meson\mesonbuild\backend\ninjabackend.py", line 1530, in generate_compile_rules
    self.generate_llvm_ir_compile_rule(compiler, True, outfile)
  File "F:\avian\meson\mesonbuild\backend\ninjabackend.py", line 1386, in generate_llvm_ir_compile_rule
    ' '.join(self.get_cross_info_lang_args(compiler, is_cross)),
  File "F:\avian\meson\mesonbuild\backend\ninjabackend.py", line 1406, in get_cross_info_lang_args
    return self.environment.cross_info.config['properties'][lang + '_args']
TypeError: unsupported operand type(s) for +: 'ClangCCompiler' and 'str'

Signed-off-by: Igor Gnatenko <i.gnatenko.brain@gmail.com>

mesonbuild/backend/ninjabackend.py

@@ -1383,7 +1383,7 @@ rule FORTRAN_DEP_HACK
             return
         rule = 'rule llvm_ir{}_COMPILER\n'.format('_CROSS' if is_cross else '')
         args = [' '.join([ninja_quote(i) for i in compiler.get_exelist()]),
-                ' '.join(self.get_cross_info_lang_args(compiler, is_cross)),
+                ' '.join(self.get_cross_info_lang_args(compiler.language, is_cross)),
                 ' '.join(compiler.get_output_args('$out')),
                 ' '.join(compiler.get_compile_only_args())]
         if mesonlib.is_windows():