Add ETH_P_IP to Fuchsia public constants

Author: smidgen2

libc-test/semver/fuchsia.txt

@@ -256,6 +256,7 @@ ERFKILL
 ESOCKTNOSUPPORT
 ESRMNT
 ESTRPIPE
+ETH_P_IP
 ETIME
 ETOOMANYREFS
 EUCLEAN

src/fuchsia/mod.rs

@@ -2677,6 +2677,9 @@ pub const PT_GNU_EH_FRAME: u32 = 0x6474e550;
 pub const PT_GNU_STACK: u32 = 0x6474e551;
 pub const PT_GNU_RELRO: u32 = 0x6474e552;
 
+// Ethernet protocol IDs.
+pub const ETH_P_IP: ::c_int = 0x0800;
+
 pub const SFD_CLOEXEC: ::c_int = 0x080000;
 
 pub const NCCS: usize = 32;