internal/rosa: key-value type

This type is used very frequently. The new type is much easier to type and can receive helper methods eventually if needed.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/kernel.go

@@ -90,7 +90,7 @@ exec /system/sbin/depmod -m /lib/modules "$@"
 `))),
 		},
 
-		Patches: [][2]string{
+		Patches: []KV{
 			{"f54a91f5337cd918eb86cf600320d25b6cfd8209", `From f54a91f5337cd918eb86cf600320d25b6cfd8209 Mon Sep 17 00:00:00 2001
 From: Nathan Chancellor <nathan@kernel.org>
 Date: Sat, 13 Dec 2025 19:58:10 +0900