Kernel: Add kokoro specific build flavors.

Add kokoro style config files to build different flavors of cos kernel.
Current use case is to build kernel with different configuration for
xfstests. This can be extended to build different kernels with different
kernel configs.

BUG=b/240174731
TEST=presubmit
RELEASE_NOTE=None
SOURCE=Internal

cos-patch: bug
Signed-off-by: Meena Shanmugam <meenashanmugam@google.com>
Change-Id: I6110a51a17f441ab1b3c5d4696a371f3e30e02c3
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/41358
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Oleksandr Tymoshenko <ovt@google.com>
(cherry picked from commit b7d34de344c1ff6947a77012332a655d5b10f7ce)
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/45370
Main-Branch-Verified: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>

google/kokoro/build_flavors/default.cfg

diff --git a/google/kokoro/build_flavors/default.cfg b/google/kokoro/build_flavors/default.cfg
new file mode 100644
index 0000000..59f085b
--- /dev/null
+++ b/google/kokoro/build_flavors/default.cfg
@@ -0,0 +1,2 @@
+KERNEL_CONFIGS="lakitu_defconfig"
+BUILD_COMPONENTS="-k -H -d"

google/kokoro/build_flavors/xfstest.cfg

diff --git a/google/kokoro/build_flavors/xfstest.cfg b/google/kokoro/build_flavors/xfstest.cfg
new file mode 100644
index 0000000..533dd32
--- /dev/null
+++ b/google/kokoro/build_flavors/xfstest.cfg
@@ -0,0 +1,2 @@
+KERNEL_CONFIGS="lakitu_defconfig,google/xfstest.config"
+BUILD_COMPONENTS="-k"