datatrak: some codings style fixes and fopen() usage

- subsurface_fopen() is needed
- translated one puts("") message
- sizeof(unsigned char | char) is always 1
- pointer symbol (*) location
- padding fixes
- braces fixes

Signed-off-by: Lubomir I. Ivanov <neolit123@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

file.c

@@ -457,7 +457,7 @@ int parse_file(const char *filename)
 	}
 
 	/* DataTrak/Wlog */
-	if (fmt && (!strcasecmp(fmt + 1, "LOG"))) {
+	if (fmt && !strcasecmp(fmt + 1, "LOG")) {
 		datatrak_import(filename, &dive_table);
 		return 0;
 	}