Put the default INT 3 vector routine well within IHSEG where it canno…

…t cause any more trouble

CHANGELOG

@@ -1,4 +1,8 @@
 NEXT
+  - Move the INT 3 default vector to well within the initial 16
+    bytes of the DOS kernel, away from the List of Lists and SFT.
+    The previous placement caused certain versions of Windows 3.2
+    (yes, the Chinese version) to crash on startup. (joncampbell123).
   - When using the running program to name screenshots and such,
     filter out all invalid characters so that Windows users can
     take snapshots even if junk characters are there (joncampbell123).

src/dos/dos_memory.cpp

@@ -581,7 +581,7 @@ void DOS_SetupMemory(void) {
 
 	assert(DOS_IHSEG != 0);
 	ihseg = DOS_IHSEG;
-	ihofs = 0xCC; /* 0xF4 conflics with SFT */
+	ihofs = 0x0E; /* DOS_IHSEG is one paragraph (16 bytes) and code below may write with negative offsets below */
 
 	real_writeb(ihseg,ihofs,(uint8_t)0xCF);		//An IRET Instruction
 	if (machine != MCH_PCJR) RealSetVec(0x02,RealMake(ihseg,ihofs)); //BioMenace (segment<0x8000). Else, taken by BIOS NMI interrupt