Fast VTOC/VVDS access reason codes

Reason Code	Description
04 (X'0004')	Mismatch between format-1 DSCB and VVR/NVR.
05 (X'0005')	FREEMAIN error (SVC 5).
08 (X'0008')	Error accessing the VTOC (CVAFFILT READ).
12 (X'000C')	Error accessing the VVDS (VVDS Manager).
32 (X'0020')	Parameter list error (eye-catcher, length, UCB address, or function requested).
64 (X'0040')	Major error (ABEND).
120 (X'0078')	GETMAIN error (SVC 120).
139 (X'008B')	CVAF error (SVC 139).