FIx compile-time issues with try convert

[reshke]

conv.c: In function ‘UtfToLocal’:
conv.c:415:43: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
415 | p = bsearch(&cutf[0], map, size1,
| ^
conv.c:452:28: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
452 | cp = bsearch(cutf, cmap, size2,
| ^
conv.c:459:35: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
459 | p = bsearch(&cutf[0], map, size1,
| ^
conv.c:466:35: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
466 | p = bsearch(&cutf[1], map, size1,
| ^
conv.c:476:27: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
476 | p = bsearch(&iutf, map, size1,
| ^
conv.c: In function ‘LocalToUtf’:
conv.c:565:19: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
565 | p = bsearch(&iiso, map, size1,
| ^
conv.c:576:36: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
576 | cp = bsearch(&iiso, cmap, size2,
| ^ поправь пожалуйста

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