ARM: omap2: hide omap3_save_secure_ram on non-OMAP3 builds

BugLink: http://bugs.launchpad.net/bugs/1756866

commit 863204cf upstream.

In configurations without CONFIG_OMAP3 but with secure RAM support,
we now run into a link failure:

arch/arm/mach-omap2/omap-secure.o: In function `omap3_save_secure_ram':
omap-secure.c:(.text+0x130): undefined reference to `save_secure_ram_context'

The omap3_save_secure_ram() function is only called from the OMAP34xx
power management code, so we can simply hide that function in the
appropriate #ifdef.

Fixes: d09220a8 ("ARM: OMAP2+: Fix SRAM virt to phys translation for save_secure_ram_context")
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry-picked from commit 1e10ddb1 v4.4.122)
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

arch/arm/mach-omap2/omap-secure.c

@@ -73,6 +73,7 @@ phys_addr_t omap_secure_ram_mempool_base(void)
 	return omap_secure_memblock_base;
 }
 
+#if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_PM)
 u32 omap3_save_secure_ram(void __iomem *addr, int size)
 {
 	u32 ret;
@@ -91,6 +92,7 @@ u32 omap3_save_secure_ram(void __iomem *addr, int size)
 
 	return ret;
 }
+#endif
 
 /**
  * rx51_secure_dispatcher: Routine to dispatch secure PPA API calls