krnl386.exe16: Avoid hardcoding array lengths.

dlls/krnl386.exe16/int21.c

@@ -336,7 +336,7 @@ static BYTE INT21_MapDrive( BYTE drive )
 {
     if (drive)
     {
-        WCHAR drivespec[3] = {'A', ':', 0};
+        WCHAR drivespec[] = {'A', ':', 0};
         UINT  drivetype;
 
         drivespec[0] += drive - 1;
@@ -359,7 +359,7 @@ static BYTE INT21_MapDrive( BYTE drive )
  */
 static void INT21_SetCurrentDrive( BYTE drive )
 {
-    WCHAR drivespec[3] = {'A', ':', 0};
+    WCHAR drivespec[] = {'A', ':', 0};
 
     drivespec[0] += drive;
 
@@ -2451,7 +2451,7 @@ static void INT21_Ioctl_Block( CONTEXT *context )
 {
     BYTE *dataptr;
     BYTE  drive = INT21_MapDrive( BL_reg(context) );
-    WCHAR drivespec[4] = {'A', ':', '\\', 0};
+    WCHAR drivespec[] = {'A', ':', '\\', 0};
     UINT  drivetype;
 
     drivespec[0] += drive;

dlls/krnl386.exe16/int25.c

@@ -82,7 +82,7 @@ BOOL DOSVM_RawRead(BYTE drive, DWORD begin, DWORD nr_sect, BYTE *dataptr, BOOL f
  */
 void WINAPI DOSVM_Int25Handler( CONTEXT *context )
 {
-    WCHAR drivespec[4] = {'A', ':', '\\', 0};
+    WCHAR drivespec[] = {'A', ':', '\\', 0};
     BYTE *dataptr = CTX_SEG_OFF_TO_LIN( context, context->SegDs, context->Ebx );
     DWORD begin;
     DWORD length;

dlls/krnl386.exe16/int26.c

@@ -71,7 +71,7 @@ BOOL DOSVM_RawWrite(BYTE drive, DWORD begin, DWORD nr_sect, BYTE *dataptr, BOOL
  */
 void WINAPI DOSVM_Int26Handler( CONTEXT *context )
 {
-    WCHAR drivespec[4] = {'A', ':', '\\', 0};
+    WCHAR drivespec[] = {'A', ':', '\\', 0};
     BYTE *dataptr = CTX_SEG_OFF_TO_LIN( context, context->SegDs, context->Ebx );
     DWORD begin;
     DWORD length;