revert PR #47351 (doesn't work)

[jgehw]

PR 47351 doesn't work as expected. The msvc_cl_debug condition would need to be checked against the toolchain, not against the compiler switch, e.g. like this:

selects.config_setting_group(
++    name = "msvc_cl_debug",
++    match_all = [
++        "@bazel_tools//src/conditions:windows_msvc",
++        ":debug",
++    ],
++    visibility = ["//visibility:public"],
++)

But even a fix like this would not lead to the desired outcome because bazel will add /DEBUG:FULL in dbg mode after /DEBUG:FASTBUILD and thus override it. The only way to compile with /DEBUG:FASTBUILD is using --compilation_mode=fastbuild or --compilation_mode=dbg --features=fastbuild. So PR 47351 is not necessary. Thus revert it.