fix: Casing of PlatformFileManager.h

[schowdhuri]

Problem

Builds on Ubuntu 20.04, UE 5 EA fail because of incorrectly cased PlatformFilemanager.h.

$ make UnrealEditor
...
...
In file included from /home/subir/UnrealEngine-5.0.0-early-access-2/Engine/Plugins/HoudiniEngine/Intermediate/Build/Linux/B4D820EA/UnrealEditor/Development/HoudiniEngineEditor/Module.HoudiniEngineEditor.3_of_3.cpp:15:
/home/subir/UnrealEngine-5.0.0-early-access-2/Engine/Plugins/HoudiniEngine/Source/HoudiniEngineEditor/Private/Tests/HoudiniEditorTestUtils.cpp:16:10: fatal error: 'Core/Public/HAL/PlatformFilemanager.h' file not found
#include "Core/Public/HAL/PlatformFilemanager.h"
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
In file included from /home/subir/UnrealEngine-5.0.0-early-access-2/Engine/Plugins/HoudiniEngine/Intermediate/Build/Linux/B4D820EA/UnrealEditor/Development/HoudiniEngineEditor/Module.HoudiniEngineEditor.1_of_3.cpp:10:
/home/subir/UnrealEngine-5.0.0-early-access-2/Engine/Plugins/HoudiniEngine/Source/HoudiniEngineEditor/Private/HoudiniEngineEditor.cpp:56:10: fatal error: 'HAL/PlatformFilemanager.h' file not found
#include "HAL/PlatformFilemanager.h"
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
In file included from /home/subir/UnrealEngine-5.0.0-early-access-2/Engine/Plugins/HoudiniEngine/Intermediate/Build/Linux/B4D820EA/UnrealEditor/Development/HoudiniEngine/Module.HoudiniEngine.3_of_5.cpp:4:
/home/subir/UnrealEngine-5.0.0-early-access-2/Engine/Plugins/HoudiniEngine/Source/HoudiniEngine/Private/HoudiniOutputTranslator.cpp:54:10: fatal error: 'HAL/PlatformFilemanager.h' file not found
#include "HAL/PlatformFilemanager.h"
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
make: *** [Makefile:1048: UnrealEditor] Error 6

Solution

Build succeeds after renaming PlatformFilemanager.h to PlatformFileManager.h.

Tested with UnrealEngine-5.0.0-early-access-2 on Ubuntu 20.04