Conv from UTF-8 to ASCII

`file *.c` to see file types (ASCII or UTF-8), convert UTF-8 (with BOM) to ASCII

```sh
sed '1s/^\xEF\xBB\xBF//'  sm4.c | iconv -f UTF-8 -t ASCII//TRANSLIT > temp.c
mv temp.c sm4.c
```

include/gmssl/endian.h

@@ -35,7 +35,7 @@
 	 (uint64_t)(p)[7])
 
 
-// 注意：PUTU32(buf, val++) 会出错！
+// WARNING: must not write PUTU32(buf, val++)
 #define PUTU16(p,V) \
 	((p)[0] = (uint8_t)((V) >> 8), \
 	 (p)[1] = (uint8_t)(V))

include/gmssl/file.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2023 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may

include/gmssl/oid.h

@@ -147,7 +147,7 @@ enum {
 	OID_aes192_cbc,
 	OID_aes256_cbc,
 
-	OID_aes128, // 没有OID
+	OID_aes128, // No OID
 
 	OID_ecdsa_with_sha1,
 	OID_ecdsa_with_sha224,

include/gmssl/pkcs8.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may
@@ -34,7 +34,7 @@ PBKDF2-params ::= SEQUENCE {
 		otherSource	AlgorithmIdentifier {{PBKDF2-SaltSources}}
 	},
 	iterationCount		INTEGER (1..MAX),
-	keyLength		INTEGER (1..MAX) OPTIONAL, -- 这个参数可以由函数指定
+	keyLength		INTEGER (1..MAX) OPTIONAL,
 	prf			AlgorithmIdentifier {{PBKDF2-PRFs}} DEFAULT algid-hmacWithSHA1
 }
 

include/gmssl/sm2.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2024 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may
@@ -45,7 +45,7 @@ from RFC 5915
 
 ECPrivateKey ::= SEQUENCE {
 	version		INTEGER,	-- value MUST be (1)
-	privateKey	OCTET STRING,	-- big endian encoding of integer 这里不是以INTEGER编码的，因此长度固定
+	privateKey	OCTET STRING,	-- big endian encoding of integer, fixed length
 	parameters	[0] EXPLICIT ECParameters OPTIONAL,
 					-- ONLY namedCurve OID is permitted, by RFC 5480
 					-- MUST always include this field, by RFC 5915

include/gmssl/sm2_key_share.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may

include/gmssl/sm2_recover.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may

include/gmssl/sm2_ring.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may

include/gmssl/tls.h

@@ -75,7 +75,7 @@ typedef enum {
 	TLS_cipher_sm4_ccm_sm3			= 0x00c7,
 
 	// TLCP, GB/T 38636-2020, GM/T 0024-2012
-	TLS_cipher_ecdhe_sm4_cbc_sm3		= 0xe011, // 可以让TLSv1.2使用这个
+	TLS_cipher_ecdhe_sm4_cbc_sm3		= 0xe011, // TODO: let TLSv1.2 use this as default cipher suite
 	TLS_cipher_ecdhe_sm4_gcm_sm3		= 0xe051,
 	TLS_cipher_ecc_sm4_cbc_sm3		= 0xe013,
 	TLS_cipher_ecc_sm4_gcm_sm3		= 0xe053,
@@ -253,8 +253,6 @@ typedef enum {
 const char *tls_curve_type_name(int type);
 
 
-// 与其支持v2，还不如直接修改v2，让v2和v3兼容
-
 typedef enum {
 	TLS_curve_secp256k1			= 22,
 	TLS_curve_secp256r1			= 23,

include/gmssl/x509.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2023 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may

include/gmssl/x509_cer.h

@@ -1,4 +1,4 @@
-/*
+/*
  *  Copyright 2014-2023 The GmSSL Project. All Rights Reserved.
  *
  *  Licensed under the Apache License, Version 2.0 (the License); you may