qt5-build.eclass: stop passing some obsolete options to configure

They were unused since the early Qt 5.0.0 days, and now upstream
officially dropped them so the configure won't accept them anymore.

See fa8dbbff8895e7e1fdf1e6b0a9f3d821cd2caf2f and
e824abd987d77efaa085fe1f9fb514d270798d55 in qtbase.

(cherry picked from proj/qt commit e7965ab4d0f98974f7abb148bcf00abafd6d698f)

eclass/qt5-build.eclass

@@ -10,7 +10,7 @@
 # @BLURB: Eclass for Qt5 split ebuilds.
 # @DESCRIPTION:
 # This eclass contains various functions that are used when building Qt5.
-# Requires EAPI 5.
+# Requires EAPI 5 or 6.
 
 case ${EAPI} in
 	5|6)	: ;;
@@ -19,7 +19,7 @@ esac
 
 inherit eutils flag-o-matic toolchain-funcs versionator virtualx
 
-if [[ ${EAPI} == 5 ]] ; then
+if [[ ${EAPI} == 5 ]]; then
 	inherit multilib
 fi
 
@@ -202,11 +202,10 @@ qt5-build_src_prepare() {
 	fi
 
 	if [[ ${EAPI} == 5 ]]; then
-		# apply patches
 		[[ ${PATCHES[@]} ]] && epatch "${PATCHES[@]}"
 		epatch_user
 	else
-		default_src_prepare
+		default
 	fi
 }
 
@@ -617,8 +616,7 @@ qt5_base_configure() {
 
 		# disable obsolete/unused X11-related flags
 		# (not shown in ./configure -help output)
-		-no-mitshm -no-xcursor -no-xfixes -no-xinerama -no-xinput
-		-no-xrandr -no-xshape -no-xsync -no-xvideo
+		-no-mitshm -no-xcursor -no-xfixes -no-xrandr -no-xshape -no-xsync
 
 		# always enable session management support: it doesn't need extra deps
 		# at configure time and turning it off is dangerous, see bug 518262