ARM: OMAP3: Fix omap3_l3_block_irq warning when CONFIG_BUG is not set

Otherwise we will get:

arch/arm/mach-omap2/omap_l3_smx.c: In function ‘omap3_l3_block_irq’:
arch/arm/mach-omap2/omap_l3_smx.c:156: warning: unused variable ‘address’
arch/arm/mach-omap2/omap_l3_smx.c:155: warning: unused variable ‘multi’
arch/arm/mach-omap2/omap_l3_smx.c:154: warning: unused variable ‘initid’
arch/arm/mach-omap2/omap_l3_smx.c:153: warning: unused variable ‘code’
arch/arm/mach-omap2/omap_l3_smx.c: At top level:
arch/arm/mach-omap2/omap_l3_smx.c:68: warning: ‘omap3_l3_code_string’ defined but not used
arch/arm/mach-omap2/omap_l3_smx.c:90: warning: ‘omap3_l3_initiator_string’ defined but not used

Fix it by always showing the L3 error.

Signed-off-by: Tony Lindgren <tony@atomide.com>