Do not inline lockutil functions

This duplicates chars in the final binary.

app/src/lockutil.c

@@ -0,0 +1,32 @@
+#include <stdlib.h>
+#include <SDL2/SDL_log.h>
+#include <SDL2/SDL_mutex.h>
+
+void mutex_lock(SDL_mutex *mutex) {
+    if (SDL_LockMutex(mutex)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not lock mutex");
+        abort();
+    }
+}
+
+void mutex_unlock(SDL_mutex *mutex) {
+    if (SDL_UnlockMutex(mutex)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not unlock mutex");
+        abort();
+    }
+}
+
+void cond_wait(SDL_cond *cond, SDL_mutex *mutex) {
+    if (SDL_CondWait(cond, mutex)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not wait on condition");
+        abort();
+    }
+}
+
+void cond_signal(SDL_cond *cond) {
+    if (SDL_CondSignal(cond)) {
+        SDL_LogCritical(SDL_LOG_CATEGORY_SYSTEM, "Could not signal a condition");
+        abort();
+    }
+}
+