[MIPS] Rewrite of setjmp/longjmp for mips64 and mipsr6

Change-Id: Idcd13413520dd503bc9cf782553675313e500a83
diff --git a/libc/arch-mips/include/machine/setjmp.h b/libc/arch-mips/include/machine/setjmp.h
index 55ba7be..a9707dc 100644
--- a/libc/arch-mips/include/machine/setjmp.h
+++ b/libc/arch-mips/include/machine/setjmp.h
@@ -5,6 +5,10 @@
 #ifndef _MIPS_SETJMP_H_
 #define _MIPS_SETJMP_H_
 
-#define	_JBLEN	157		/* size, in longs, of a jmp_buf */
+#ifdef __LP64__
+#define	_JBLEN	22		/* size, in 8-byte longs, of a mips64 jmp_buf */
+#else
+#define	_JBLEN	29		/* size, in 4-byte longs, of a mips32 jmp_buf */
+#endif
 
 #endif /* !_MIPS_SETJMP_H_ */