dump: eliminate DumpState.page_shift ("guest's page shift")

dump: eliminate DumpState.page_shift ("guest's page shift")

Just use TARGET_PAGE_BITS.

"DumpState.page_shift" used to have type "uint32_t", while the replacement
TARGET_PAGE_BITS has type "int". Since "DumpState.page_shift" was only
used as bit shift counts in the paddr_to_pfn() and pfn_to_paddr() macros,
this is safe.

Suggested-by: Paolo Bonzini <[email protected]>
Signed-off-by: Laszlo Ersek <[email protected]>
Reviewed-by: Paolo Bonzini <[email protected]>
Signed-off-by: Luiz Capitulino <[email protected]>