efi: stmm: Drop unneeded null pointer check

The API documenation of setup_mm_hdr does not mention that dptr can be
NULL, this is a local function, and no caller passes NULL. So drop the
unneeded check.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Author: jan-kiszka

drivers/firmware/efi/stmm/tee_stmm_efi.c

@@ -185,8 +185,7 @@ static void *setup_mm_hdr(u8 **dptr, size_t payload_size, size_t func)
 
 	var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data;
 	var_hdr->function = func;
-	if (dptr)
-		*dptr = comm_buf;
+	*dptr = comm_buf;
 
 	return var_hdr->data;
 }