Install vintf_fragments/init_rc along with targets

Even though `m foo` installs vintf_fragments and init_rc files. There
was no direct dependency from the installed target to
vintf_fragments/init_rc files.

With the following:

cc_binary {
  name: "foo",
  vintf_fragments: ["foo.xml"]
}

`m out/target/product/vsoc_x86_64/system/bin/foo` didn't install
foo.xml.

This change adds the order-only deps from the target install to
vintf_fragments/init_fc files.

Bug: 198818343
Test: (see above)
Change-Id: I4656d43d15407a85fea7c95b22e4bbe19fb86aee