dsp: base: Allow PLDM File Transfer use MultipartReceive decode API

MultipartReceive command in DSP0240 1.2.0 allow different PLDM Type
to use. DfRead command of PLDM File Transfer protocol (DSP0242 1.0.0)
is one of the specific implementation of MultipartReceive.

Change-Id: I806d16a1a21bcb2b3bee5b590db2280710e624b6
Signed-off-by: John Chung <john.chung@arm.com>
diff --git a/src/dsp/base.c b/src/dsp/base.c
index c1bf63d..ee2cd04 100644
--- a/src/dsp/base.c
+++ b/src/dsp/base.c
@@ -546,7 +546,8 @@
 	struct pldm_multipart_receive_req *request =
 		(struct pldm_multipart_receive_req *)msg->payload;
 
-	if (request->pldm_type != PLDM_BASE) {
+	if (request->pldm_type != PLDM_BASE &&
+	    request->pldm_type != PLDM_FILE) {
 		return PLDM_ERROR_INVALID_PLDM_TYPE;
 	}