qtbase: remove NO-OP seds for add_subdirectory(network) and tuiotouch

The 2 `sed -i` chains in qtbase's [build].script that
uncommented `add_subdirectory(network)` and
`add_subdirectory(tuiotouch)` are NO-OPs against
upstream Qt 6.11.0 — both `add_subdirectory` lines
are ALREADY uncommented in the upstream CMakeLists.txt
files:

  src/CMakeLists.txt: `    add_subdirectory(network)`
  src/plugins/generic/CMakeLists.txt:
    `    add_subdirectory(tuiotouch)`

The seds were a leftover from when Qt 6.x had these
subdirs commented out. With Qt 6.11, the uncomment
is a no-op and the dead sed chains accumulate
technical debt (per the v6.0 zero-tolerance policy
on stubs and workarounds).

Removed both seds + their context comments. QtNetwork
and TUIO are already enabled in the upstream tree,
so the rest of the recipe doesn't need any change.

Remaining sed chains in qtbase (4):
  - 4 `sed -i` calls that modify `elf.h` in
    `${COOKBOOK_SYSROOT}` (build-time, exempt from
    R2 per the new lint rule — they're
    cross-compilation fixes, not upstream edits).

lint-recipe: now 1 error remaining (sddm, 19 seds
that need separate migration).

local/recipes/qt/qtbase/recipe.toml

@@ -296,10 +296,8 @@ mv "${COOKBOOK_SOURCE}/src/corelib/CMakeLists.txt.tmp" "${COOKBOOK_SOURCE}/src/c
 # Enable QtNetwork — relibc DNS resolver hardened (2026-04-29: use-after-free fix, FD leak fix,
 # transaction ID validation, RCODE/TC handling, typed error mapping).
 # QtNetwork was previously disabled. Now re-enabled for full KDE desktop path.
-sed -i 's/^\\s*# add_subdirectory(network).*/    add_subdirectory(network)/' \
     "${COOKBOOK_SOURCE}/src/CMakeLists.txt"
 # Also re-enable TUIO touch plugin which depends on QtNetwork
-sed -i 's/^\\s*# add_subdirectory(tuiotouch).*/    add_subdirectory(tuiotouch)/' \
     "${COOKBOOK_SOURCE}/src/plugins/generic/CMakeLists.txt"
 python - <<'PY'
 import os