Remove some non-ASCII symbols from a comment.

Buildfarm member hamerkop is unhappy that daitch_mokotoff.c "contains
a character that cannot be represented in the current code page
(932). Save the file in Unicode format to prevent data loss".  There
are a lot of non-ASCII characters in comments, but I do not see any
outside a comment, so this is just cosmetic.  Nonetheless the warning
is fairly scary and people might waste time trying to understand the
cause, so we ought to silence it.

We have only one other occurrence of a non-ASCII character in .c or .h
files in the tree: predicate.c mentions "Uwe Röhm".  It's far from
clear why hamerkop isn't complaining about that too; but it isn't,
so maybe there is some special provision for accented Roman letters.
We can remove the non-letter symbols from the comment for
iso8859_1_to_ascii_upper without any real loss of usefulness,
so let's try that first to see if it silences the warning.

Discussion: https://postgr.es/m/1546512.1681495035@sss.pgh.pa.us

contrib/fuzzystrmatch/daitch_mokotoff.c

@@ -112,7 +112,7 @@ static const dm_codes end_codes[2] =
 /* Mapping from ISO8859-1 to upper-case ASCII, covering the range 0x60..0xFF. */
 static const char iso8859_1_to_ascii_upper[] =
 /*
-"`abcdefghijklmnopqrstuvwxyz{|}~                                  ¡¢£¤¥¦§¨©ª«¬ ®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ"
+"`abcdefghijklmnopqrstuvwxyz{|}~                                  ¡.....various odd symbols.....¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ*ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö/øùúûüýþÿ"
 */
 "`ABCDEFGHIJKLMNOPQRSTUVWXYZ{|}~                                  !                             ?AAAAAAECEEEEIIIIDNOOOOO*OUUUUYDSAAAAAAECEEEEIIIIDNOOOOO/OUUUUYDY";