[NTVDM] Trivial english typos fixes.

subsystems/mvdm/ntvdm/bios/vidbios.c

@@ -2357,7 +2357,7 @@ static VOID VidBiosSetCursorShape(WORD CursorStartEnd)
      * https://sites.google.com/site/pcdosretro/biosdata
      *
      * A proof that it is OK is that in the following code samples it is
-     * explicitely mentioned that setting bit 0 disables cursor emulation:
+     * explicitly mentioned that setting bit 0 disables cursor emulation:
      * - Code snippets in PC Magazine vol.5 num.15 of 16/09/1986, p.291-292;
      * - CardFile DOS utility (Jeff Prosise, PC Magazine vol.6 num.17 of 13/10/1987, p.403-416):
      *   https://ia600700.us.archive.org/1/items/srccode-00000020/cardfile.asm.txt

subsystems/mvdm/ntvdm/dos/dos32krnl/himem.c

@@ -435,7 +435,7 @@ static VOID WINAPI XmsBopProcedure(LPWORD Stack)
                 break;
             }
 
-            // NOTE: We implicitely suppose that we always have HMA.
+            // NOTE: We implicitly suppose that we always have HMA.
             // If not, we should fail there with the XMS_STATUS_HMA_DOES_NOT_EXIST
             // error code.
 

subsystems/mvdm/ntvdm/dos/dos32krnl/process.c

@@ -673,7 +673,7 @@ DWORD DosLoadExecutableInternal(IN DOS_EXEC_TYPE LoadType,
 
         /*
          * Keep critical flags, clear test flags (OF, SF, ZF, AF, PF, CF)
-         * and explicitely set the interrupt flag.
+         * and explicitly set the interrupt flag.
          */
         setEFLAGS((getEFLAGS() & ~0x08D5) | 0x0200);