rust: bundle Cargo.lock

Cargo.lock has to be provided as template, Cargo.lock.in so it can
live beside Cargo.lock in out of tree automake builds, like distcheck.

This will pin Rust dependencies even for git builds, updating
Cargo.lock will now be a manual process that we'll have to take care
of periodically.

configure.ac

@@ -2561,7 +2561,7 @@ AC_SUBST(enable_non_bundled_htp)
 
 AM_CONDITIONAL([BUILD_SHARED_LIBRARY], [test "x$enable_shared" = "xyes"] && [test "x$can_build_shared_library" = "xyes"])
 
-AC_CONFIG_FILES(Makefile src/Makefile rust/Makefile rust/Cargo.toml rust/derive/Cargo.toml rust/.cargo/config)
+AC_CONFIG_FILES(Makefile src/Makefile rust/Makefile rust/Cargo.lock rust/Cargo.toml rust/derive/Cargo.toml rust/.cargo/config)
 AC_CONFIG_FILES(qa/Makefile qa/coccinelle/Makefile)
 AC_CONFIG_FILES(rules/Makefile doc/Makefile doc/userguide/Makefile)
 AC_CONFIG_FILES(contrib/Makefile contrib/file_processor/Makefile contrib/file_processor/Action/Makefile contrib/file_processor/Processor/Makefile)

rust/.gitignore

@@ -1,4 +1,5 @@
 !Cargo.toml.in
+!Cargo.lock.in
 Cargo.toml
 /.cargo/config
 /Cargo.lock

rust/Makefile.am

@@ -97,3 +97,9 @@ dist/rust-bindings.h:
 else
 dist/rust-bindings.h:
 endif
+
+Cargo.toml: Cargo.toml.in
+
+update-lock: Cargo.toml
+	cargo update
+	mv Cargo.lock Cargo.lock.in