Add *CARD as an alternative to *MMFS

[hoglet67]

This will cost 7 bytes.

diff --git a/mmfs100.asm b/mmfs100.asm
index 0c30e4c..b68b707 100644
--- a/mmfs100.asm
+++ b/mmfs100.asm
@@ -1345,6 +1345,8 @@ ENDIF
        EQUB &80
        EQUS "MMFS"
        EQUB &80
+       EQUS "CARD"
+       EQUB &80
        BRK

        \ COMMAND TABLE 3               ; HELP
@@ -1431,6 +1433,7 @@ ENDIF
        EQUW CMD_DISC-1
        EQUW CMD_DISC-1
        EQUW CMD_CARD-1
+       EQUW CMD_CARD-1
        EQUW NotCmdTable22-1

 .cmdaddr3

Currently, the SWMMFS ROMs are petty tight on space:

Building U/SWMMFS...
    code ends at &B5F4  ( 10 bytes free ) 
    mdsum is b9c7c2e3cfb0ac53bcaad953e3e2ce4e -
Building T/SWMMFS...
    code ends at &B5F8  ( 6 bytes free ) 
    mdsum is a3195bef1bcb4cc05caf8e72516a974a -

So we'll have to do some optimization before this will fit.

Dave