INT 2F - CS_TSR specification - GET PROCESS BLOCK BY PROCESS HANDLE

	AX = 8002h
	BX = process handle for TSR (see AX=8001h"CS_TSR")
Return: ES:DI -> process block for specified TSR (see #02928)
		unchanged if no match for process handle
Note:	This function is used to allocate a process handle when the TSR
	  installs itself, by setting ES:DI to point at something other than
	  a CS_TSR process block's signature string and iterating through the
	  possible process handles (0001h to FFFFh) until ES:DI is returned
	  unchanged
SeeAlso: AX=8000h"CS_TSR",AX=8001h"CS_TSR",AX=8003h"CS_TSR"