termux-api: free malloc'ed child_argv array on execv error

We exit right after so this is not exactly strictly necessary, but
that might change at some point and is good practise in any case.

Author: Grimler91

termux-api.c

@@ -275,6 +275,8 @@ _Noreturn void exec_am_broadcast(int argc, char** argv,
     // Use an a executable taking care of PATH and LD_LIBRARY_PATH:
     execv(PREFIX "/bin/am", child_argv);
 
+    // We should not reach here, if we do, then free memory we malloc'ed
+    free(child_argv);
     perror("execv(\"" PREFIX "/bin/am\")");
     exit(1);
 }