Fix: add correct feature flags

Author: alamb

datafusion/core/Cargo.toml

@@ -51,8 +51,10 @@ default = [
     "datetime_expressions",
     "encoding_expressions",
     "regex_expressions",
+    "math_expressions",
     "string_expressions",
     "unicode_expressions",
+    "unparser",
     "compression",
     "parquet",
     "recursive_protection",
@@ -75,6 +77,7 @@ recursive_protection = [
 ]
 serde = ["dep:serde"]
 string_expressions = ["datafusion-functions/string_expressions"]
+unparser = ["datafusion-sql/unparser"]
 unicode_expressions = [
     "datafusion-sql/unicode_expressions",
     "datafusion-functions/unicode_expressions",