nios2: Name architecture correctly in endian.h header

Nios II is not i386 :-)

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>

libc/sysdeps/linux/nios2/bits/endian.h

@@ -1,4 +1,4 @@
-/* i386 is little-endian.  */
+/* Nios II is little-endian.  */
 
 #ifndef _ENDIAN_H
 # error "Never use <bits/endian.h> directly; include <endian.h> instead."