More SD Card Compatibility Changes

Based on a logic analyzer trace from Andy Cooper, it appears that some SD cards want the unused CRC byte of the command packet to be 0xFF instead of the 0x00 filler I was using.  Changed to put 0xFF in the CRC byte when unused.

Source/HBIOS/sd.asm

@@ -1320,6 +1320,8 @@ SD_INITCMD1:
 	INC	HL			; POINT TO NEXT BYTE
 	LD	(HL),A			; CLEAR IT
 	DJNZ	SD_INITCMD1		; LOOP TILL DONE
+	DEC	A			; $FF TO ACCUM
+	LD	(SD_CMDCRC),A		; PUT $FF IN CRC POSITION
 	RET
 ;
 ; EXECUTE APP COMMAND

Source/ver.inc

@@ -2,4 +2,4 @@
 #DEFINE	RMN	1
 #DEFINE	RUP	1
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.1.1-pre.26"
+#DEFINE BIOSVER	"3.1.1-pre.27"

Source/ver.lib

@@ -3,5 +3,5 @@ rmn	equ	1
 rup	equ	1
 rtp	equ	0
 biosver	macro
-	db	"3.1.1-pre.26"
+	db	"3.1.1-pre.27"
 	endm