Add github.com/google/cppdap as a third_party dependency

Used by the new Vulkan debugger.

Bug: b/145351270
Change-Id: I4419fa208b52ed2db17422e3c14fe01dfb55cde9
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/38889
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Ben Clayton <bclayton@google.com>

.gitmodules

diff --git a/.gitmodules b/.gitmodules
index a94ba42..391b6f4 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,7 @@
+[submodule "third_party/cppdap"]
+	path = third_party/cppdap
+	url = https://github.com/google/cppdap
+
 [submodule "third_party/googletest"]
 	path = third_party/googletest
 	url = https://github.com/google/googletest.git

third_party/cppdap

diff --git a/third_party/cppdap b/third_party/cppdap
new file mode 160000
index 0000000..eab43f3
--- /dev/null
+++ b/third_party/cppdap
@@ -0,0 +1 @@
+Subproject commit eab43f3518ab3dbf7f74573085918b139933464f