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

fusl/src/signal/mips/sigsetjmp.s

Index: fusl/src/signal/mips/sigsetjmp.s
diff --git a/fusl/src/signal/mips/sigsetjmp.s b/fusl/src/signal/mips/sigsetjmp.s
new file mode 100644
index 0000000000000000000000000000000000000000..74b65ff68f2593cb7f4c0c2143f7813ecbd04db6
--- /dev/null
+++ b/fusl/src/signal/mips/sigsetjmp.s
@@ -0,0 +1,33 @@
+.set noreorder
+
+.global sigsetjmp
+.global __sigsetjmp
+.type sigsetjmp,@function
+.type __sigsetjmp,@function
+sigsetjmp:
+__sigsetjmp:
+	lui $gp, %hi(_gp_disp)
+	addiu $gp, %lo(_gp_disp)
+	beq $5, $0, 1f
+	 addu $gp, $gp, $25
+
+	sw $ra, 104($4)
+	sw $16, 104+4+16($4)
+
+	lw $25, %call16(setjmp)($gp)
+	jalr $25
+	 move $16, $4
+
+	move $5,$2
+	move $4,$16
+	lw $ra, 104($4)
+	lw $16, 104+4+16($4)
+
+.hidden __sigsetjmp_tail
+	lw $25, %call16(__sigsetjmp_tail)($gp)
+	jr $25
+	 nop
+
+1:	lw $25, %call16(setjmp)($gp)
+	jr $25
+	 nop