Add a "fork" of musl as //fusl.

fusl/src/thread/pthread_getschedparam.c

Index: fusl/src/thread/pthread_getschedparam.c
diff --git a/fusl/src/thread/pthread_getschedparam.c b/fusl/src/thread/pthread_getschedparam.c
new file mode 100644
index 0000000000000000000000000000000000000000..3053c1865e0a1f1d2c6c8ea16d30ecdcddfb4a7d
--- /dev/null
+++ b/fusl/src/thread/pthread_getschedparam.c
@@ -0,0 +1,17 @@
+#include "pthread_impl.h"
+
+int pthread_getschedparam(pthread_t t, int *restrict policy, struct sched_param *restrict param)
+{
+	int r;
+	__lock(t->killlock);
+	if (t->dead) {
+		r = ESRCH;
+	} else {
+		r = -__syscall(SYS_sched_getparam, t->tid, param);
+		if (!r) {
+			*policy = __syscall(SYS_sched_getscheduler, t->tid);
+		}
+	}
+	__unlock(t->killlock);
+	return r;
+}