Do not install android.hardware.hardware_keystore.xml outside apex

`android.hardware.security.keymint-service.nonsecure` is part of
`com.android.hardware.keymint.rust_nonsecure` apex. However, listing
android.hardware.hardware_keystore.xml in `required` of the binary
installs two copies of this permission file on device - one inside the
apex, and another it the /vendor/etc/permission (outside the apex).

With  this CL, the latter will no longer be installed. This CL is
motivated by having the vendor.img building with soong as part of mk->bp
migration.

Test: m com.android.hardware.keymint.rust_nonsecure
Test: deapexer list
out/target/product/vsoc_x86_64/vendor/apex/com.android.hardware.keymint.rust_nonsecure.apex
 # verified that etc/permissions/android.hardware.hardware_keystore.xml
 is present

Bug: 374371755
Bug: 376110962
Change-Id: I15ba92c81296f869277940767ff3a76c28214c18

security/keymint/aidl/default/Android.bp

@@ -97,9 +97,6 @@ rust_binary {
         "libkmr_hal_nonsecure",
         "libkmr_ta_nonsecure",
     ],
-    required: [
-        "android.hardware.hardware_keystore.xml",
-    ],
     vintf_fragment_modules: [
         "android.hardware.security.keymint-service.xml",
         "android.hardware.security.sharedsecret-service.xml",