Fix Android thread priority

Android threads are Linux threads which differ from the POSIX standard. Calling pthread_setschedparam does not produce the intended effect on Android.

src/sfizz/FilePool.cpp

@@ -42,6 +42,8 @@
 #include <atomic_queue/defs.h>
 #if defined(_WIN32)
 #include <windows.h>
+#elif defined(__ANDROID__)
+#include <sys/resource.h>
 #else
 #include <pthread.h>
 #endif
@@ -609,6 +611,13 @@ void sfz::FilePool::raiseCurrentThreadPriority() noexcept
         std::system_error error(GetLastError(), std::system_category());
         DBG("[sfizz] Cannot set current thread priority: " << error.what());
     }
+#elif defined(__ANDROID__)
+    int tid = gettid();  // Android specific function to get thread ID
+    int priority = -20;  // Highest priority for nice value
+    if (setpriority(PRIO_PROCESS, tid, priority) != 0) {
+        // setpriority sets errno on failure
+        DBG("[sfizz] Cannot set current thread priority: " << strerror(errno));
+    }
 #else
     pthread_t thread = pthread_self();
     int policy;