build: Add and build Kaldi submodule.

.gitmodules

@@ -58,3 +58,7 @@
 [submodule "openfst"]
 	path = openfst
 	url = https://github.com/alphacep/openfst
+[submodule "kaldi"]
+	path = kaldi
+	url = https://github.com/alphacep/kaldi
+	branch = vosk

Makefile.in

@@ -425,6 +425,29 @@ $(eval $(call rules-autoconf,openfst,32))
 $(eval $(call rules-autoconf,openfst,64))
 
 
+##
+## kaldi
+##
+
+KALDI_SOURCE_ARGS = \
+  --exclude src/**/CMakeLists.txt \
+
+KALDI_CMAKE_ARGS = \
+  -DKALDI_VERSION=5.5-proton \
+  -DBLAS_LIBRARIES=-lblas \
+  -DLAPACK_LIBRARIES=-llapack \
+  -DCMAKE_POSITION_INDEPENDENT_CODE=ON \
+  -DBUILD_SHARED_LIBS=OFF \
+  -DKALDI_BUILD_TEST=OFF \
+  -DKALDI_BUILD_EXE=OFF \
+
+KALDI_DEPENDS = openfst
+
+$(eval $(call rules-source,kaldi,$(SRCDIR)/kaldi))
+$(eval $(call rules-cmake,kaldi,32))
+$(eval $(call rules-cmake,kaldi,64))
+
+
 ##
 ## wine
 ##