Min mem to 8192 + voltage min/max fix in XML

i see that with min mem 4096 RAM drop to 8MB and then recover
and system is unstable in high load.

with 8192 set, min ram drop only to 14MB~16MB then go up.
system much more stable.
Fixed SEC ROM data + cache fix on boot! + set static mmap_min_addr
as requested by JB ROM = 32768
Added new JB SAMMY ROM Support I9100JHLS4 Thanks @jgjd691995