ANDROID: kleaf: convert fips140 to kleaf

As a result of this change:

- fips140 is no longer part of the GKI build but a
  separate module, so it is not signed
  (CONFIG_MODULE_SIG_ALL is not set)

- GKI images (e.g. system_dlkm image, boot images)
  etc. are no longer part of the build -- because
  they are unnecessary.

- The build config no longer inherits from build.config.gki.aarch64
  directly to avoid building unnecessary system_dklm, boot images,
  GKI artifacts, etc.

Test: BUILD_CONFIG=common/build.config.gki.aarch64.fips140 build/build.sh
Test: tools/bazel build //common:fips140_dist
Bug: 232083350

Change-Id: I2cb0ee0b55c2a5ea46e6d73ecad4aa97585c1989
Signed-off-by: Yifan Hong <elsk@google.com>