CMake: Correctly unset host page size if set via cache

Fixes x86 flatpak builds unnecessarily using dynamic page size.

CMakeModules/DuckStationUtils.cmake

@@ -120,8 +120,11 @@ function(detect_page_size)
   # For universal Apple builds, we use preprocessor macros to determine page size.
   # Similar for Windows, except it's always 4KB.
   if(NOT CPU_ARCH_ARM64 OR NOT LINUX)
+    unset(HOST_PAGE_SIZE CACHE)
     unset(HOST_PAGE_SIZE PARENT_SCOPE)
+    unset(HOST_MIN_PAGE_SIZE CACHE)
     unset(HOST_MIN_PAGE_SIZE PARENT_SCOPE)
+    unset(HOST_MAX_PAGE_SIZE CACHE)
     unset(HOST_MAX_PAGE_SIZE PARENT_SCOPE)
     return()
   elseif(DEFINED HOST_PAGE_SIZE)
@@ -168,6 +171,7 @@ endfunction()
 function(detect_cache_line_size)
   # This is only needed for ARM64, or if the user hasn't overridden it explicitly.
   if(NOT CPU_ARCH_ARM64 OR HOST_CACHE_LINE_SIZE)
+    unset(HOST_CACHE_LINE_SIZE CACHE)
     unset(HOST_CACHE_LINE_SIZE PARENT_SCOPE)
     return()
   endif()