Add opus patches

Signed-off-by: falkTX <falktx@falktx.com>

patches/opus/01_force-libs.patch

@@ -0,0 +1,10 @@
+--- opus-static-1.1.orig/opus.pc.in
++++ opus-static-1.1/opus.pc.in
+@@ -11,6 +11,6 @@ URL: http://opus-codec.org/
+ Version: @VERSION@
+ Requires:
+ Conflicts:
+-Libs: -L${libdir} -lopus
++Libs: -L${libdir} -lopus -lm
+ Libs.private: @LIBM@
+ Cflags: -I${includedir}/opus

patches/opus/02_hidden-opus-api.patch

@@ -0,0 +1,23 @@
+--- opus-static-1.3.1.orig/include/opus_defines.h
++++ opus-static-1.3.1/include/opus_defines.h
+@@ -63,19 +63,7 @@ extern "C" {
+ /** @cond OPUS_INTERNAL_DOC */
+ /**Export control for opus functions */
+ 
+-#ifndef OPUS_EXPORT
+-# if defined(WIN32)
+-#  if defined(OPUS_BUILD) && defined(DLL_EXPORT)
+-#   define OPUS_EXPORT __declspec(dllexport)
+-#  else
+-#   define OPUS_EXPORT
+-#  endif
+-# elif defined(__GNUC__) && defined(OPUS_BUILD)
+-#  define OPUS_EXPORT __attribute__ ((visibility ("default")))
+-# else
+-#  define OPUS_EXPORT
+-# endif
+-#endif
++#define OPUS_EXPORT
+ 
+ # if !defined(OPUS_GNUC_PREREQ)
+ #  if defined(__GNUC__)&&defined(__GNUC_MINOR__)