drm/panfrost: Remove type name from internal structs

The two structs internal to struct panfrost_dump_object_header were
named, but sadly that is incompatible with C++, causing an error: "an
anonymous union may only have public non-static data members".

However nothing refers to struct pan_reg_hdr and struct pan_bomap_hdr
and there's no need to export these definitions, so lets drop them. This
fixes the C++ build error with the minimum change in userspace API.
Reported-by: Adrián Larumbe <adrian.larumbe@collabora.com>
Fixes: 730c2bf4 ("drm/panfrost: Add support for devcoredump")
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221017104602.142992-2-steven.price@arm.com

include/uapi/drm/panfrost_drm.h

@@ -242,7 +242,7 @@ struct panfrost_dump_object_header {
 	__le32 file_offset;
 
 	union {
-		struct pan_reg_hdr {
+		struct {
 			__le64 jc;
 			__le32 gpu_id;
 			__le32 major;
@@ -250,7 +250,7 @@ struct panfrost_dump_object_header {
 			__le64 nbos;
 		} reghdr;
 
-		struct pan_bomap_hdr {
+		struct {
 			__le32 valid;
 			__le64 iova;
 			__le32 data[2];