run: use 'upvar' instead of 'global'

Using 'upvar' instead of 'global' in the 'append_if' and 'lappend_if'
functions makes it possible to use these functions with local variables
of the calling function.

Fixes #1137.
base: interface for D- and I-cache synchronization

On ARM, when machine instructions get written into the data cache
(for example by a JIT compiler), one needs to make sure that the
instructions get written out to memory and read from memory into
the instruction cache before they get executed. This functionality
is usually provided by a kernel syscall and this patch adds a generic
interface for Genode applications to use it.

Fixes #1153.
Qt5: ARM-related improvements

- fix compile errors when building for ARM
- use the correct device drivers in Qt run scripts

Fixes #1154.