Fix doxygen issue:

1) comment for structure should be in doxygen format, such as /// , /**, /*!
2) comment for data field of structure should in doxygen format.
3) should not exist blank between ") (" when declaring a type of function point.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5364 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Include/Protocol/Mtftp4.h

@@ -466,7 +466,7 @@ EFI_STATUS
 **/
 typedef
 EFI_STATUS
-(EFIAPI *EFI_MTFTP4_POLL) (
+(EFIAPI *EFI_MTFTP4_POLL)(
   IN EFI_MTFTP4_PROTOCOL       *This
   )
 ;