OvmfPkg/LoadLinuxLib: list "LoadLinuxLib.h" in the INF file

OvmfPkg/LoadLinuxLib: list "LoadLinuxLib.h" in the INF file

The header file declares the InitLinuxDescriptorTables() and
SetLinuxDescriptorTables() functions, which are called from "Linux.c" and
implemented in "LinuxGdt.c".

The header file also declares the JumpToKernel() and JumpToUefiKernel()
functions, which are similarly called from "Linux.c". They are implemented
(dependent on architecture) in "Ia32/JumpToKernel.nasm" and
"X64/JumpToKernel.nasm".

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
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>