mfsGetRomFileNum
mfsGetRamFileNum


Format:	s32 mfsRamGetFileNum(MfsDirID dirID,u16 attr)
	s32 mfsRomGetFileNum(MfsDirID dirID,u16 attr)
Arguments:	dirID		Directory ID of directory
	attr		File or directory specification (logical OR can be taken)
			MFS_FILE_ATTR_FILE		File
			MFS_FILE_ATTR_DIRECTORY		Directory

Return value:Number of files (a negative value is an error)
Function:	Obtains the number of files belonging to the specified directory
Description:	This function obtains the number of files or directory files in the directory specified by dirID.
When MFS_ALL_FILES is specified for dirID, this function returns the total number of files or directories in the RAM or ROM area.

Main errors:
	MFS_ERR_NOTMFSDISK Not an MFS-format disk
			The disk ID's disk use is not 1, or the header is different. 
	MFS_ERR_VERSION	Different version disk 
	MFS_ERR_PROTECT	Write protected
			The medium is volume protected.