linux-user: Define ELF_ET_DYN_BASE in $guest/target_mman.h

Copy each guest kernel's default value, then bound it
against reserved_va or the host address space.

Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
23 files changed