OvmfPkg/QemuVideoDxe: list "UnalignedIoInternal.h" in the INF file

The header file declares the UnalignedIoWrite32() and UnalignedIoRead32()
functions. The functions are called from VmwareSvgaWrite() and
VmwareSvgaRead() in the common "Driver.c" source file. The
UnalignedIo*32() functions are defined with inline assembly, C-language
compiler intrinsics, or as ASSERT(FALSE), in distinct C files, dependent
on architecture and toolchain.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Phil Dennis-Jordan <phil@philjordan.eu>
Suggested-by: Michael Kinney <michael.d.kinney@intel.com>
Ref: http://mid.mail-archive.com/E92EE9817A31E24EB0585FDF735412F56327F7D3@ORSMSX113.amr.corp.intel.com
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>