RBIL61 - INT 2F - DOS 3.0+ internal - NORMALIZE ASCIZ FILENAME {undocumented}

INT 2F U - DOS 3.0+ internal - NORMALIZE ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. FILENAME
	AX = 1211h
	DS:SI -> ASCIZA NUL-terminated ASCII string.	The ASCIZ string "ABC" consists of the four bytes 41h, 42h, 43h, and 00h.  Unless otherwise specified, maximum lengths given in the interrupt list do not include the terminating NUL. filename to normalize
	ES:DI -> buffer for normalized filename
Return: destination buffer filled with uppercase filename, with slashes turned
	to backslashes
SeeAlso: AX=121Eh,AX=1221h