platform: Reinforce some symbol names

This commit rename some symbol names for base APIs to reinforce API
naming convention defined here [1]. The list of change includes:

1. `struct pldm_file_descriptor_pdr` to
    `struct pldm_platform_file_descriptor_pdr`
2. `decode_pldm_file_descriptor_pdr()` to
    `decode_pldm_platform_file_descriptor_pdr()`

[1]: https://github.com/openbmc/libpldm/blob/main/docs/checklists/changes.md#adding-a-new-api

Change-Id: I76bd12fa59a7d61d450d9d36cbf091b39101faa8
Signed-off-by: Chau Ly <chaul@amperecomputing.com>
diff --git a/src/dsp/platform.c b/src/dsp/platform.c
index 297a033..9af2d67 100644
--- a/src/dsp/platform.c
+++ b/src/dsp/platform.c
@@ -3473,8 +3473,9 @@
 }
 
 LIBPLDM_ABI_TESTING
-int decode_pldm_file_descriptor_pdr(const void *data, size_t data_length,
-				    struct pldm_file_descriptor_pdr *pdr)
+int decode_pldm_platform_file_descriptor_pdr(
+	const void *data, size_t data_length,
+	struct pldm_platform_file_descriptor_pdr *pdr)
 {
 	PLDM_MSGBUF_DEFINE_P(buf);
 	int rc;