Remove some ioctls from being defined for gnu/mips.

Seems like not all arches/c-libraries like having every ioctl defined.  These ioctls were previously defined for musl, but not gnu.  I similarly had to removed defining an ioctl for x86 that had not been previously defined. Maybe will run into more issues after this one. Maybe need to undefine this ioctol for all arches and not just mips.  Plan to squash all commits once done.

Author: lancethepants

src/unix/linux_like/linux/arch/mips/mod.rs

@@ -155,8 +155,6 @@ pub const TCGETS2: ::Ioctl = 0x4030542a;
 pub const TCSETS2: ::Ioctl = 0x8030542b;
 pub const TCSETSW2: ::Ioctl = 0x8030542c;
 pub const TCSETSF2: ::Ioctl = 0x8030542d;
-pub const TIOCGRS485: ::Ioctl = 0x4020542e;
-pub const TIOCSRS485: ::Ioctl = 0xc020542f;
 pub const TIOCGPTN: ::Ioctl = 0x40045430;
 pub const TIOCSPTLCK: ::Ioctl = 0x80045431;
 pub const TIOCGDEV: ::Ioctl = 0x40045432;
@@ -188,6 +186,13 @@ pub const TIOCGETP: ::Ioctl = 0x7408;
 pub const TIOCSETP: ::Ioctl = 0x7409;
 pub const TIOCSETN: ::Ioctl = 0x740a;
 
+cfg_if! {
+    if #[cfg(target_env = "musl")] {
+        pub const TIOCGRS485: ::Ioctl = 0x4020542e;
+        pub const TIOCSRS485: ::Ioctl = 0xc020542f;
+    }
+}
+
 pub const TIOCM_LE: ::c_int = 0x001;
 pub const TIOCM_DTR: ::c_int = 0x002;
 pub const TIOCM_RTS: ::c_int = 0x004;