data(kana): one sokuon rule for every doubled consonant, and the missing hira rows

Hiragana spelled out 42 doubled syllables (kka, ssha, ttsu, ...) and so
knew none it did not list: matcha, baggu and beddo came out as ma-tc-ha,
ba-gg-u. Katakana already used the engine's small-tsu rule for a few
doubles. Both maps now list every doubled consonant but n, plus tch, and
hiragana gains di, che and fa/fi/fe/fo like katakana.

tests/engine_test.c

@@ -1065,6 +1065,8 @@ engine_japanese_readings(struct ct *t)
 		char *want;
 	} replay[] = {
 		{ "kitte", "きって" },
+		{ "matcha", "まっちゃ" },
+		{ "baggu", "ばっぐ" },
 		{ "kanj", "かんj" },
 		{ "n'ya", "んや" },
 	};
@@ -1189,6 +1191,7 @@ engine_katakana_sequences(struct ct *t)
 		{ "katta", "カッタ" },
 		{ "gakkou", "ガッコウ" },
 		{ "matcha", "マッチャ" },
+		{ "baggu", "バッグ" },
 		{ "xu", "ゥ" },
 		{ "vu", "ヴ" },
 	};