.SHELLFLAGS is extended by option pipefail to make pipes fail if any pipe
element fails. As .SHELLFLAGS is exported into sub-make instances it
must be unexported before calling third-party build systems recursively.
* Drivers have to use lx_kit/memory_dma.cc
* Protocol-stacks use lx_kit/memory_non_dma.cc
* Moreover the device-dependent lx_emul parts get removed
from the common lx_emul import rules
Fix#4443
This commit contains:
* Minimal Linux kernel target: pc_linux
* Library to generate a Linux build directory, config, generated headers
* API depot package
The actual work was provided by Josef Soentgen.
Ref genodelabs/genode#4416