Fix a few compiler warnings

Most of which made sense.

src/browser.c

@@ -90,7 +90,7 @@ static void browse_draw_info(struct dir *dr) {
 static void browse_draw_item(struct dir *n, int row) {
   char ct, dt, *size, gr[11], *items;
   int i, o, x;
-  float pc;
+  float pc = 0.0f;
 
   if(n->flags & FF_BSEL)
     attron(A_REVERSE);

src/exclude.c

@@ -108,10 +108,10 @@ void exclude_clear() {
 #define CACHEDIR_TAG_SIGNATURE "Signature: 8a477f597d28d172789f06886806bc55"
 
 int has_cachedir_tag(const char *name) {
-  static path_l = 1024;
+  static int path_l = 1024;
   static char *path = NULL;
   int l;
-  const int signature_l = sizeof CACHEDIR_TAG_SIGNATURE - 1;
+  const size_t signature_l = sizeof CACHEDIR_TAG_SIGNATURE - 1;
   char buf[signature_l];
   FILE *f;
   int match = 0;