[llvm] [libc][bazel] Allow configure options to alter all targets (PR #89251)

[Guillaume Chatelet via llvm-commits]

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@@ -3228,7 +3213,7 @@ libc_support_library(
 libc_support_library(
     name = "printf_mock_parser",
     hdrs = ["src/stdio/printf_core/parser.h"],
-    defines = PRINTF_COPTS + ["LIBC_COPT_MOCK_ARG_LIST"],
+    defines = ["LIBC_COPT_MOCK_ARG_LIST"],
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gchatelet wrote:

So after discussing this internally a bit I think we want to remove all `define`s from LLVM libc.
We should really use `local_define` to make the configuration internal and not leak preprocessor definitions to the outside world.

The [documentation](https://bazel.build/reference/be/c-cpp#cc_binary.defines) is quite clear as well: 
`Be very careful, since this may have far-reaching effects. When in doubt, add define values to "local_defines" instead.`

https://github.com/llvm/llvm-project/pull/89251