SUNRPC: remove redundant pointer plainhdr

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Pointer plainhdr is being assigned a value that is never read, the
pointer is redundant and can be removed.
Signed-off-by: NColin Ian King <colin.i.king@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

net/sunrpc/auth_gss/gss_krb5_wrap.c

@@ -409,7 +409,7 @@ static u32
 gss_wrap_kerberos_v2(struct krb5_ctx *kctx, u32 offset,
 		     struct xdr_buf *buf, struct page **pages)
 {
-	u8		*ptr, *plainhdr;
+	u8		*ptr;
 	time64_t	now;
 	u8		flags = 0x00;
 	__be16		*be16ptr;
@@ -426,7 +426,7 @@ gss_wrap_kerberos_v2(struct krb5_ctx *kctx, u32 offset,
 		return GSS_S_FAILURE;
 
 	/* construct gss token header */
-	ptr = plainhdr = buf->head[0].iov_base + offset;
+	ptr = buf->head[0].iov_base + offset;
 	*ptr++ = (unsigned char) ((KG2_TOK_WRAP>>8) & 0xff);
 	*ptr++ = (unsigned char) (KG2_TOK_WRAP & 0xff);