mpm/hs: fix compile warnings

CC       util-mpm-hs-cache.o
util-mpm-hs-cache.c:301:59: error: implicit conversion loses integer precision: '__size_t' (aka 'unsigned long') to 'uint32_t'
      (aka 'unsigned int') [-Werror,-Wshorten-64-to-32]
  301 |         SCSha256Update(hasher, (const uint8_t *)ref_info, strlen(ref_info));
      |         ~~~~~~~~~~~~~~                                    ^~~~~~~~~~~~~~~~
util-mpm-hs-cache.c:310:46: error: implicit conversion loses integer precision: 'size_t' (aka 'unsigned long') to 'uint32_t'
      (aka 'unsigned int') [-Werror,-Wshorten-64-to-32]
  310 |     if (!SCSha256FinalizeToHex(hasher, hash, hash_len)) {
      |          ~~~~~~~~~~~~~~~~~~~~~               ^~~~~~~~
2 errors generated.

src/util-mpm-hs-cache.c

@@ -298,7 +298,7 @@ int HSHashDb(const PatternDatabase *pd, char *hash, size_t hash_len)
     SCMutexLock(&g_hs_ref_info_mutex);
     const char *ref_info = HSGetReferenceDbInfo();
     if (ref_info != NULL) {
-        SCSha256Update(hasher, (const uint8_t *)ref_info, strlen(ref_info));
+        SCSha256Update(hasher, (const uint8_t *)ref_info, (uint32_t)strlen(ref_info));
     }
     SCMutexUnlock(&g_hs_ref_info_mutex);
 
@@ -307,7 +307,7 @@ int HSHashDb(const PatternDatabase *pd, char *hash, size_t hash_len)
         SCHSCachePatternHash(pd->parray[i], hasher);
     }
 
-    if (!SCSha256FinalizeToHex(hasher, hash, hash_len)) {
+    if (!SCSha256FinalizeToHex(hasher, hash, (uint32_t)hash_len)) {
         hasher = NULL;
         SCLogDebug("sha256 hashing failed");
         return -1;