atrusctl: use unversioned libchrome libraray.

Libchrome is changing pkg-config and .so library name from
xxxx-${libbase_ver}.{pc,so} to xxx.{pc,so}.

Libchrome uprev rebuild will be handled by ebuild subslot change. And
there's no need to install multiple libchrome. Keeping libbase_ver
suffix will cause troubles on linking libraries when developers wants to
test locally emerge a-single-package without build_packages, after a
libchrome uprev. Especially in a case a package depends on another
package(library), and both depends on libchrome. Thus, removing
libbase_ver from suffix.

BUG=chromium:920513
TEST=CQ

Change-Id: I02d2147906c7da7fc24996f3ec1ed866c067f8f3
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/atrusctl/+/2500784
Reviewed-by: Joe Tessler <jrt@chromium.org>
Commit-Queue: Qijiang Fan <fqj@google.com>
Tested-by: Qijiang Fan <fqj@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 6a233e9..48ad200 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -41,7 +41,7 @@
   configs += [ ":atrusd_config" ]
   pkg_deps = [
     "libbrillo",
-    "libchrome-${libbase_ver}",
+    "libchrome",
     "libudev",
     "libusb-1.0",
   ]