temp: Remove static from kernel_device_frames

This symbol is possibly optimised out by the compiler because it is
static and usually only has a few entries. The seL4CP tool depends on
this symbol existing in the ELF.

The real solution is to have `c_header.py` or another script that
generates the array to also export the kernel device frames in a
format that is easily readable by external tools.

tools/hardware/outputs/c_header.py

@@ -71,7 +71,7 @@
 {% endfor %}
 
 {% if len(kernel_regions) > 0 %}
-static const kernel_frame_t BOOT_RODATA kernel_device_frames[] = {
+const kernel_frame_t BOOT_RODATA kernel_device_frames[] = {
     {% for group in kernel_regions %}
     {% if group.has_macro() %}
     {{ group.get_macro() }}