fix the mremap signature

The mremap definition was incorrect (unsigned long instead of int) and
it was missing the optional new_address parameter.

Change-Id: Ib9d0675aaa098c21617cedc9b2b8cf267be3aec4
diff --git a/libc/arch-mips/syscalls/mremap.S b/libc/arch-mips/syscalls/___mremap.S
similarity index 84%
rename from libc/arch-mips/syscalls/mremap.S
rename to libc/arch-mips/syscalls/___mremap.S
index 7cbb94e..82e2eb3 100644
--- a/libc/arch-mips/syscalls/mremap.S
+++ b/libc/arch-mips/syscalls/___mremap.S
@@ -2,7 +2,7 @@
 
 #include <private/bionic_asm.h>
 
-ENTRY(mremap)
+ENTRY(___mremap)
     .set noreorder
     .cpload t9
     li v0, __NR_mremap
@@ -16,4 +16,5 @@
     j t9
     nop
     .set reorder
-END(mremap)
+END(___mremap)
+.hidden ___mremap