Early log panic does not print logs

[nordic-krch]

Describe the bug
When log_panic is triggered early,before log thread starts, no logs can be printed because logger backends are initialized in the logger thread.

To Reproduce
Modified hello_world:

#include <zephyr.h>
#include <misc/printk.h>
#include <logging/log.h>
LOG_MODULE_REGISTER(app);
void main(void)
{
	LOG_INF("test");
	k_panic();
	printk("Hello World! %s\n", CONFIG_BOARD);
}

Expected behavior
On uart console test log entry should be seen followed by kernel panic report.

Impact
Early failures are hard to debug.