tests: Fix doc validator script

Script was intolerant of unicode characters that now show up in the
spec.

Change-Id: I125f12139eec395ffc8ae61e92de1428fa2ac0c6
diff --git a/scripts/vk_validation_stats.py b/scripts/vk_validation_stats.py
index 36346b3..58c5c0b 100755
--- a/scripts/vk_validation_stats.py
+++ b/scripts/vk_validation_stats.py
@@ -103,7 +103,7 @@
         """Read a database file into internal data structures, format of each line is <enum><implemented Y|N?><testname><api><errormsg><notes>"""
         #db_dict = {} # This is a simple db of just enum->errormsg, the same as is created from spec
         #max_id = 0
-        with open(self.db_file, "r") as infile:
+        with open(self.db_file, "r", encoding="utf8") as infile:
             for line in infile:
                 line = line.strip()
                 if line.startswith('#') or '' == line: