s390/fpu: add documentation about fpu helper functions

Add documentation which describes what the fpu helper functions are
good for, and why they should be used.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This commit is contained in:
Heiko Carstens 2024-02-03 11:45:03 +01:00
commit 045bad0800