EmbeddedPkg/VirtualRealTimeClockLib: Fix VS2022 type conversion warnings

Fix type conversion warnings (C4244) in VirtualRealTimeClockLib that
prevent it from building with Visual Studio 2022 when the /WX flag
(treat warnings as errors) is enabled.

Changes made:

EmbeddedPkg/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c
  - Add (UINTN) casts for DivU64x64Remainder return values in LibGetTime()
  - Add (UINTN) casts for DivU64x64Remainder return values in LibSetTime()

Rationale:
- DivU64x64Remainder returns UINT64 values
- On IA32 architecture, UINTN is 32-bit while the return value is 64-bit
- Explicit casts are required to handle the 64-bit to 32-bit conversion
  on IA32 without data loss warnings
- The casts are safe because the values represent elapsed seconds since
  platform reset, which will not overflow 32-bit values in practice

Tested on:
- Windows 11 with VS2022 (X64 and IA32)
- Ubuntu with GCC5 (X64)

Addresses: #11737

Signed-off-by: Gary Beihl <[email protected]>

Author: garybeihl

EmbeddedPkg/Library/VirtualRealTimeClockLib/VirtualRealTimeClockLib.c

@@ -98,7 +98,7 @@ LibGetTime (
   }
 
   Counter       = GetPerformanceCounter ();
-  EpochSeconds += DivU64x64Remainder (Counter, Freq, &Remainder);
+  EpochSeconds += (UINTN)DivU64x64Remainder (Counter, Freq, &Remainder);
 
   // Get the current time zone information from non-volatile storage
   Size   = sizeof (TimeZone);
@@ -271,8 +271,8 @@ LibSetTime (
   Freq = GetPerformanceCounterProperties (NULL, NULL);
   if (Freq != 0) {
     Counter = GetPerformanceCounter ();
-    if (EpochSeconds > DivU64x64Remainder (Counter, Freq, &Remainder)) {
-      EpochSeconds -= DivU64x64Remainder (Counter, Freq, &Remainder);
+    if (EpochSeconds > (UINTN)DivU64x64Remainder (Counter, Freq, &Remainder)) {
+      EpochSeconds -= (UINTN)DivU64x64Remainder (Counter, Freq, &Remainder);
     }
   }