Cleanup screen.spec

I hope this cleanup changes can make spec file more simple and accurate with Fedora packaging guidelines.

screen.spec

@@ -4,14 +4,12 @@
 Summary:        A screen manager that supports multiple logins on one terminal
 Name:           screen
 Version:        4.6.1
-Release:        3%{?dist}
+Release:        4%{?dist}
 License:        GPLv2+
-Group:          Applications/System
 URL:            http://www.gnu.org/software/screen
 Requires(pre):  /usr/sbin/groupadd
 Requires(preun): /sbin/install-info
 Requires(post): /sbin/install-info
-BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 BuildRequires:  ncurses-devel pam-devel libutempter-devel autoconf texinfo
 BuildRequires:  automake
 # for %%_tmpfilesdir macro
@@ -41,14 +39,7 @@ support multiple logins on one terminal.
 
 
 %prep
-%setup -q -n %{name}-%{version}
-%patch1 -p1 -b .libs
-%patch2 -p1 -b .screenrc
-%patch3 -p1 -b .E3
-%patch4 -p1 -b .suppress_remap
-%patch5 -p1 -b .crypto
-%patch6 -p1 -b .texinpatch
-%patch7 -p1 -b .xterm
+%autosetup -p1
 
 %build
 ./autogen.sh
@@ -109,9 +100,6 @@ EOF
 # Remove files from the buildroot which we don't want packaged
 rm -f $RPM_BUILD_ROOT%{_infodir}/dir
 
-%clean
-rm -rf $RPM_BUILD_ROOT
-
 %pre
 /usr/sbin/groupadd -g 84 -r -f screen
 :
@@ -127,7 +115,6 @@ fi
 :
 
 %files
-%defattr(-,root,root,-)
 %doc README doc/FAQ doc/README.DOTSCREEN ChangeLog
 %license COPYING
 %{_mandir}/man1/screen.*
@@ -145,6 +132,9 @@ fi
 %endif
 
 %changelog
+* Sun Sep 10 2017 Vasiliy N. Glazov <vascom2@gmail.com> - 4.6.1-4
+- Cleanup spec
+
 * Thu Aug 03 2017 Fedora Release Engineering <releng@fedoraproject.org> - 4.6.1-3
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_27_Binutils_Mass_Rebuild