Drop drive letter from path to razor root when RAZOR_ROOT set.

If the RAZOR_ROOT environment variable was set to eg., /root then on
Microsoft Windows we were trying to use paths such as /rootC:/Programs
which is obviously wrong. Instead we should drop the drive letter
giving paths of the form /root/Programs. Note that the drive letter is
_not_ migrated to C:/root/Programs: If a root of C:/root was desired
then RAZOR_ROOT would have been set to C:/root.

%define _source_payload w9.gzdio

%define _binary_payload w9.gzdio

Name:      zap

Summary:   Test package

Group:     Test

License:   GPL

Version:   1

Release:   1

Source:    zap.tar

BuildArch: noarch

BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)

Prefix:    /usr

%description

Test package

%prep

%build

%install

mkdir -p $RPM_BUILD_ROOT/usr/bin

touch $RPM_BUILD_ROOT/usr/bin/zap

%clean

%files

/usr/bin/zap