Merge branch 'net-visibility-of-memory-limits-in-netns'

Matteo Croce says:

====================
net: visibility of memory limits in netns

Some programs need to know the size of the network buffers to operate
correctly, export the following sysctls read-only in network namespaces:

- net.core.rmem_default
- net.core.rmem_max
- net.core.wmem_default
- net.core.wmem_max
====================

Link: https://lore.kernel.org/r/20240530232722.45255-1-technoboy85@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>