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

fusl/src/termios/cfmakeraw.c

Index: fusl/src/termios/cfmakeraw.c
diff --git a/fusl/src/termios/cfmakeraw.c b/fusl/src/termios/cfmakeraw.c
new file mode 100644
index 0000000000000000000000000000000000000000..c9dddc12a0ff67e60a5d1379447bec9173e165c1
--- /dev/null
+++ b/fusl/src/termios/cfmakeraw.c
@@ -0,0 +1,13 @@
+#define _GNU_SOURCE
+#include <termios.h>
+
+void cfmakeraw(struct termios *t)
+{
+	t->c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON);
+	t->c_oflag &= ~OPOST;
+	t->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
+	t->c_cflag &= ~(CSIZE|PARENB);
+	t->c_cflag |= CS8;
+	t->c_cc[VMIN] = 1;
+	t->c_cc[VTIME] = 0;
+}