Minor, use a meaningful naming in template parameter (#1582)

diff --git a/src/hb-ot-layout.hh b/src/hb-ot-layout.hh
index b2b5ec2..5125e9f 100644
--- a/src/hb-ot-layout.hh
+++ b/src/hb-ot-layout.hh
@@ -215,7 +215,7 @@
   unsigned int gen_cat = (unsigned int) unicode->general_category (u);
   unsigned int props = gen_cat;
 
-  if (u >= 0x80)
+  if (u >= 0x80u)
   {
     buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII;
 
@@ -232,10 +232,10 @@
        * FVSes are GC=Mn, we have use a separate bit to remember them.
        * Fixes:
        * https://github.com/harfbuzz/harfbuzz/issues/234 */
-      else if (unlikely (hb_in_range<uint32_t> (u, 0x180Bu, 0x180Du))) props |= UPROPS_MASK_HIDDEN;
+      else if (unlikely (hb_in_range<hb_codepoint_t> (u, 0x180Bu, 0x180Du))) props |= UPROPS_MASK_HIDDEN;
       /* TAG characters need similar treatment. Fixes:
        * https://github.com/harfbuzz/harfbuzz/issues/463 */
-      else if (unlikely (hb_in_range<uint32_t> (u, 0xE0020u, 0xE007Fu))) props |= UPROPS_MASK_HIDDEN;
+      else if (unlikely (hb_in_range<hb_codepoint_t> (u, 0xE0020u, 0xE007Fu))) props |= UPROPS_MASK_HIDDEN;
       /* COMBINING GRAPHEME JOINER should not be skipped; at least some times.
        * https://github.com/harfbuzz/harfbuzz/issues/554 */
       else if (unlikely (u == 0x034Fu))