Fix -Werror=conversion failure in trimcr().

While here avoid a separate strlen call in read_repos(), using the
length returned by trimcr().  The check for a NULL buf is removed as it
was already tested earlier in the function.

fsops.c

@@ -139,10 +139,7 @@ read_repos(void)
 			}
 		}
 
-		if (trimcr(buf) < 0) /* strip newline */
-			continue;
-
-		curlen = strlen(buf) + 2; /* ' ' + '\0' */
+		curlen = trimcr(buf) + 2; /* ' ' + '\0' */
 		repolen += curlen;
 
 		repos = xrealloc(repos, repolen * sizeof(char));

tools.c

@@ -48,13 +48,13 @@ charcount(char *str, char c)
 /*
  * Remove trailing \n or \r\n, returning length of resulting string.
  */
-int
+size_t
 trimcr(char *str)
 {
 	size_t len;
 
 	if (str == NULL)
-		return (-1);
+		return (0);
 
 	len = strlen(str);
 

tools.h

@@ -158,7 +158,7 @@ extern uint8_t yesflag;
 extern uint8_t noflag;
 
 extern int charcount(char *, char);
-extern int trimcr(char *);
+extern size_t trimcr(char *);
 extern void free_list(char **);
 extern void do_log(const char *, const char *, ...);
 extern void trunc_str(char *, char, int);