add prebuilt_kernel_modules module

prebuilt_kernel_modules is a build rule for processing and installing
kernel module files. The module files are processed by depmod to build
modules.{load|alias|deps|softdeps} files. Debug symbols are stripped
from the module files and then all the files are installed to
./lib/modules/<kernel_version> directory.

This is the Soong-equivalent of the 'build-image-kernel-modules-dir`
macro and is expected to replace it in the future.

Bug: 178980227
Test: m

Change-Id: I772ac816824921d275869e35b93a083d239a2450
diff --git a/kernel/Android.bp b/kernel/Android.bp
new file mode 100644
index 0000000..f8a48d9
--- /dev/null
+++ b/kernel/Android.bp
@@ -0,0 +1,18 @@
+bootstrap_go_package {
+    name: "soong-kernel",
+    pkgPath: "android/soong/kernel",
+    deps: [
+        "blueprint",
+        "soong",
+        "soong-android",
+        "soong-cc",
+        "soong-cc-config",
+    ],
+    srcs: [
+        "prebuilt_kernel_modules.go",
+    ],
+    testSrcs: [
+        "prebuilt_kernel_modules_test.go",
+    ],
+    pluginFor: ["soong_build"],
+}