ARM: OMAP4: Make L4SEC clock domain SWSUP only

Commit c2ce5fb3 ('ARM: OMAP: DRA7xx: Make L4SEC clock domain SWSUP
only') made DRA7 SoC L4SEC clock domain SWSUP only because of power
state transition issues detected with HWSUP mode. Based on
experimentation similar issue exists on OMAP4, so do the same change
for OMAP4 also.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>