Add new export LLM config (#11511)

This PR was created by the merge bot to help merge the original PR into
the main branch.
ghstack PR number: #11028 by
@jackzhxng
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ghstack PR base:
https://github.com/pytorch/executorch/tree/gh/jackzhxng/10/base
ghstack PR head:
https://github.com/pytorch/executorch/tree/gh/jackzhxng/10/head
Merge bot PR base: https://github.com/pytorch/executorch/tree/main
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https://github.com/pytorch/executorch/tree/gh/jackzhxng/10/orig
@diff-train-skip-merge

Co-authored-by: Jack Zhang <[email protected]>

Author: pytorchbot

examples/models/llama/config/TARGETS

@@ -0,0 +1,9 @@
+# Any targets that should be shared between fbcode and xplat must be defined in
+# targets.bzl. This file can contain fbcode-only targets.
+
+load("@fbsource//xplat/executorch/build:runtime_wrapper.bzl", "runtime")
+load(":targets.bzl", "define_common_targets")
+
+oncall("executorch")
+
+define_common_targets()