swr: fix shared lib build

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

configure

@@ -3476,6 +3476,7 @@ get_version(){
 }
 
 get_version LIBSWSCALE  libswscale/swscale.h
+get_version LIBSWRESAMPLE libswresample/swresample.h
 get_version LIBPOSTPROC libpostproc/postprocess.h
 get_version LIBAVCODEC  libavcodec/version.h
 get_version LIBAVDEVICE libavdevice/avdevice.h

libswresample/Makefile

@@ -9,4 +9,4 @@ OBJS = swresample.o audioconvert.o resample2.o rematrix.o
 
 TESTPROGS = swresample_test
 
-include $(SUBDIR)../subdir.mak
+include $(SRC_PATH)/subdir.mak

libswresample/libswresample.v

+LIBSWRESAMPLE_$MAJOR {
+        global: swr_*; ff_*;
+        local: *;
+};