Remove incorrect usage of "ASCII" and "ANSI"

Windows-1252 was sometimes being referred to as ASCII or ANSI
in Dolphin, which is incorrect. ASCII is only a subset of
Windows-1252, and ANSI is (rather improperly) used in Windows
to refer to the current code page (which often is 1252 on
Western systems, but can also be something entirely different).

The commit also replaces "SJIS" with "Shift JIS". "SJIS"
isn't misleading, but "Shift JIS" is more commonly used.

Data/Sys/GC/font-licenses.txt

@@ -1,4 +1,4 @@
-The two fonts in this directory (font_ansi.bin and font_sjis.bin) were
+The two fonts in this directory (font_western.bin and font_japanese.bin) were
 generated using gc-font-tool which can be found in the docs/ directory in the
 dolphin source code.