OvmfPkg/XenHypercallLib: Remove unused HobLib Commit 0e6f6c715c59 removed the use of gEfiXenInfoGuid. Fixes: 0e6f6c715c59 ("OvmfPkg/XenHypercallLib: Use direct hypercalls") Signed-off-by: Anthony PERARD <anthony.perard@vates.tech>