pem.c: fix copy and paste mistake from 55d030089b

src/pem.c

@@ -43,22 +43,26 @@ readline(char *line, int line_size, FILE * fp)
 {
     size_t len;
 
-    if (!*line) {
+    if (!line) {
         return -1;
     }
     if (!fgets(line, line_size, fp)) {
         return -1;
     }
 
+    if (*line) {
         len = strlen(line);
         if (len > 0 && line[len - 1] == '\n') {
             line[len - 1] = '\0';
         }
+    }
 
+    if (*line) {
         len = strlen(line);
         if (len > 0 && line[len - 1] == '\r') {
             line[len - 1] = '\0';
         }
+    }
 
     return 0;
 }