build : fix OpenBLAS detection under Arch Linux (ggml-org#1173)

Author: marmistrz

CMakeLists.txt

@@ -156,6 +156,7 @@ if (WHISPER_BLAS)
         if(BLAS_FOUND)
             message(STATUS "BLAS compatible library found")
             message(STATUS "Libraries ${BLAS_LIBRARIES}")
+            find_path(BLAS_INCLUDE_DIRS cblas.h /usr/include/openblas /usr/local/include/openblas $ENV{BLAS_HOME}/include)
             set(WHISPER_EXTRA_FLAGS ${WHISPER_EXTRA_FLAGS} -DGGML_USE_OPENBLAS)
             include_directories(${BLAS_INCLUDE_DIRS})
             set(WHISPER_EXTRA_LIBS ${WHISPER_EXTRA_LIBS} ${BLAS_LIBRARIES})

Makefile

@@ -139,7 +139,7 @@ endif
 endif
 
 ifdef WHISPER_OPENBLAS
-	CFLAGS  += -DGGML_USE_OPENBLAS -I/usr/local/include/openblas
+	CFLAGS  += -DGGML_USE_OPENBLAS -I/usr/local/include/openblas -I/usr/include/openblas
 	LDFLAGS += -lopenblas
 endif