find_all: Remove redundant check if Stratis device
find_all: Remove redundant check if Stratis device

We already know that all the devices we are iterating over are
Stratis devices, so simply retrieve the pool_uuid from them.

Signed-off-by: Tony Asleson <1ef2d381aa56d512126ddaacc29e68136e4fdf55@redhat.com>

trgill/stratisd,trgill/stratisd,stratis-storage/stratisd,stratis-storage/stratisd,mulkieran/stratisd,mulkieran/stratisd,stratis-storage/stratisd