MT#55283 remove pointless mkdir

This is implied by the preceding `install` commands

Change-Id: Ia50aa8016247a31f35eec25cfb7d3a694c5a7cb1

el/rtpengine.spec

@@ -174,7 +174,6 @@ install -D -p -m644 kernel-module/xt_RTPENGINE.c \
 	 %{buildroot}%{_usrsrc}/%{name}-%{version}-%{release}/xt_RTPENGINE.c
 install -D -p -m644 kernel-module/xt_RTPENGINE.h \
 	 %{buildroot}%{_usrsrc}/%{name}-%{version}-%{release}/xt_RTPENGINE.h
-mkdir -p %{buildroot}%{_usrsrc}/%{name}-%{version}-%{release}
 install -D -p -m644 debian/ngcp-rtpengine-kernel-dkms.dkms %{buildroot}%{_usrsrc}/%{name}-%{version}-%{release}/dkms.conf
 sed -i -e "s/#MODULE_VERSION#/%{version}-%{release}/g" %{buildroot}%{_usrsrc}/%{name}-%{version}-%{release}/dkms.conf
 %if 0%{?with_transcoding} > 0