Build sherpa-onnx as a single shared library (#1078)

When `-D BUILD_SHARED_LIBS=ON` is passed to `cmake`, it builds a single shared library.

Specifically, 

- For C APIs, it builds `libsherpa-onnx-c-api.so`
- For Python APIs, it builds `_sherpa_onnx.cpython-xx-xx.so`
- For Kotlin and Java APIs, it builds `libsherpa-onnx-jni.so`

There is no `libsherpa-onnx-core.so` any longer.

Note it affects only shared libraries.

cmake/portaudio.cmake

@@ -26,13 +26,9 @@ function(download_portaudio)
     endif()
   endforeach()
 
-  if(BUILD_SHARED_LIBS)
-    set(PA_BUILD_SHARED ON CACHE BOOL "" FORCE)
-    set(PA_BUILD_STATIC OFF CACHE BOOL "" FORCE)
-  else()
-    set(PA_BUILD_SHARED OFF CACHE BOOL "" FORCE)
-    set(PA_BUILD_STATIC ON CACHE BOOL "" FORCE)
-  endif()
+  # Always use static build
+  set(PA_BUILD_SHARED OFF CACHE BOOL "" FORCE)
+  set(PA_BUILD_STATIC ON CACHE BOOL "" FORCE)
 
   FetchContent_Declare(portaudio
     URL
@@ -55,28 +51,17 @@ function(download_portaudio)
 
   add_subdirectory(${portaudio_SOURCE_DIR} ${portaudio_BINARY_DIR} EXCLUDE_FROM_ALL)
 
-  if(BUILD_SHARED_LIBS)
-    set_target_properties(portaudio PROPERTIES OUTPUT_NAME "sherpa-onnx-portaudio")
-    if(NOT WIN32)
-      target_compile_options(portaudio PRIVATE "-Wno-deprecated-declarations")
-    endif()
-
-    if(SHERPA_ONNX_ENABLE_PYTHON AND WIN32)
-      install(TARGETS portaudio DESTINATION ..)
-    else()
-      install(TARGETS portaudio DESTINATION lib)
-    endif()
-  else()
-    set_target_properties(portaudio_static PROPERTIES OUTPUT_NAME "sherpa-onnx-portaudio_static")
-    if(NOT WIN32)
-      target_compile_options(portaudio_static PRIVATE "-Wno-deprecated-declarations")
-    endif()
-    if(SHERPA_ONNX_ENABLE_PYTHON AND WIN32)
-      install(TARGETS portaudio_static DESTINATION ..)
-    else()
-      install(TARGETS portaudio_static DESTINATION lib)
-    endif()
+  set_target_properties(portaudio_static PROPERTIES OUTPUT_NAME "sherpa-onnx-portaudio_static")
+  if(NOT WIN32)
+    target_compile_options(portaudio_static PRIVATE "-Wno-deprecated-declarations")
   endif()
+
+  if(NOT BUILD_SHARED_LIBS AND SHERPA_ONNX_ENABLE_BINARY)
+    install(TARGETS
+      portaudio_static
+    DESTINATION lib)
+  endif()
+
 endfunction()
 
 download_portaudio()