OvmfPkg/QemuBootOrderLib: Fix NOOPT build failure

OvmfPkg/QemuBootOrderLib: Fix NOOPT build failure

This patch is to fix the IA32/NOOPT/VS Toolchain build failure.
The VS2015 failure log as below:
QemuBootOrderLib.lib(ExtraRootBusMap.obj) :
error LNK2001: unresolved external symbol __allmul
s:\..\Build\OvmfIa32\NOOPT_VS2015\IA32\MdeModulePkg\
Universal\BdsDxe\BdsDxe\DEBUG\BdsDxe.dll :
fatal error LNK1120: 1 unresolved externals
NMAKE : fatal error U1077:
'"C:\Program Files\Microsoft Visual Studio 14.0\Vc\bin\link.exe"' :
return code '0x460'
Stop.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>