Remove dependency of strlcat()

There was only one place where `strlcat` was used, and `snprintf`
actually does a better job at what the code was trying to achieve.

Signed-off-by: Antonio Niño Díaz <[email protected]>

include/extern/strl.h

@@ -16,9 +16,7 @@
 #else /* STRL_IN_LIBC */
 
 #define strlcpy rgbds_strlcpy
-#define strlcat rgbds_strlcat
 size_t strlcpy(char *dst, const char *src, size_t dsize);
-size_t strlcat(char *dst, const char *src, size_t dsize);
 
 #endif /* STRL_IN_LIBC */