treewide: adjust local CMakeLists.txt min version to cmake 4.x

treewide: adjust local CMakeLists.txt min version to cmake 4.x

cmake 4.x will require 'cmake_minimum_required' defined in cmake
projects to be at least 3.5. Adjust those local sources where that
variable is currently defined with value below 3.5.

Use 3.30 as the value, as 3.30 is currently used in 24.10, the oldest
still supported OpenWrt release branch.

Signed-off-by: Hannu Nyman <[email protected]>