Linker scripts not working properly on xtensa

[zycz]

Problem:
There is a problem with xtensa linker script. Compiler does not see linker script added in cmake with zephyr_linker_sources on xtensa platform.

To reproduce:
If you create linker file (for example test.ld and create some marker there) and add it in cmake using:
zephyr_linker_sources(SECTIONS test.ld)
it works perfectly well on all platforms but xtensa (this marker can be visible in zephyr.map).

To reproduce it you can also use this PR: #38611
and try to run Event Manager sample (it uses linker script in such way) on any xtensa platform.

Solution?:
Adding: #include <snippets-sections.ld> in soc/xtensa/sample_controller/linker.ld solves the problem.
Do not know if it was not added on purpose or because of mistake?