Trivial: Style fix

make the style checker happy

seL4_libs: remove autoconf.h from seL4_libs

this commit removes autoconf.h generation from each lib and
append '#include <<lib_name>/gen_config.h>' after each
'#include <autoconf.h>' since autoconf.h is only the for the
kernel config now. This is a temporarily solution, since we
currently don't have a way to tell which header files each file
is trying to include when it includes 'autoconf.h'

libsel4utils: transition to new libelf API

sel4utils: Add comments and fields to elf_region_t

This structure is for tracking the underlying reservation for an elf
segment. However because segments can overlap the same frame, we need
to be more careful about how to handle reservation layout. The new
fields make it possible to keep track of the actual elf segment layout
and also adjustments for the underlying reservation.

When loading the elf data into a vspace it is necessary to have all the
regions because now the start or end of a segment may be in a
reservation belonging to an adjacent region. The convention is that
all the regions will exist in an ordered array to handle these
conditions.

Use pragma in elf.h

SELFOUR-1083 Store name in test case and use C89, add elf_get_section

The test name is stored inside the testcase struct in order to make it
simpler to extract the test cases from sel4test-tests.

I changed the DEFINE_TEST_WITH_TYPE macro to use C89 instead of C99
style assignment because the domains.cxx (C++) tests would not compile
with C99-style assignment for strings.

I added sel4utils_elf_get_section() so that sel4test-driver can extract
the section containing test cases from sel4test-tests.

libsel4utils: Provide wrappers for retrieving ELF program headers

Fix licenses

Remove #ifdef guards for the existance of different libraries

These libraries are now all part of this same repository, and so they will always exist.
Guarding for them adds unnecessary complexity

SELFOUR-567: use seL4_CapRights_t

libsel4utils: Mark some strings as const.