proposal: Use standard integer types for static keywords

src/libstrongswan/crypto/proposal/proposal_keywords_static.txt

@@ -25,8 +25,8 @@
 struct proposal_token {
 	char             *name;
 	transform_type_t  type;
-	u_int16_t         algorithm;
-	u_int16_t         keysize;
+	uint16_t          algorithm;
+	uint16_t          keysize;
 };
 %%
 null,             ENCRYPTION_ALGORITHM, ENCR_NULL,                 0