* coding.c (Fdefine_coding_system_internal): Don't redeclare 'i' inside

* coding.c (Fdefine_coding_system_internal): Don't redeclare 'i' inside

a block, when the outer 'i' will do.
(decode_coding_utf_8, decode_coding_utf_16, detect_coding_emacs_mule):
(emacs_mule_char, decode_coding_emacs_mule, detect_coding_iso_2022):
(decode_coding_iso_2022, decode_coding_sjis, decode_coding_big5):
(decode_coding_raw_text, decode_coding_charset, get_translation_table):
(Fdecode_sjis_char, Fdefine_coding_system_internal):
Rename locals to avoid shadowing.
* character.h (FETCH_STRING_CHAR_ADVANCE): Likewise.