Tuna: update to LeanKernel 5.4 stable

Oops removed ramdisk part

Change-Id: I23bb4e2328e2b84bc4d477ed62dbadd33289b9e4
Signed-off-by: Gergely Szell (sethyx) <szell@hu.ibm.com>
Bump kernel to LeanKernel 5.8

Change-Id: Ia6d1f15d45eb5d51e189e4604748e28977083e9b
Signed-off-by: Gergely Szell (sethyx) <szell@hu.ibm.com>