mips64: add missing symbols

Add O_LARGEFILE define to src/unix/linux_like/linux/musl/b64/mips64.rs
Signed-off-by: Donald Hoskins <[email protected]>

Author: Grommish

src/unix/linux_like/linux/musl/b64/mips64.rs

@@ -458,6 +458,7 @@ pub const O_SYNC: ::c_int = 0x4010;
 pub const O_RSYNC: ::c_int = 0x4010;
 pub const O_DSYNC: ::c_int = 0x10;
 pub const O_ASYNC: ::c_int = 0x1000;
+pub const O_LARGEFILE: ::c_int = 0;
 
 pub const EDEADLK: ::c_int = 45;
 pub const ENAMETOOLONG: ::c_int = 78;