ARM: vexpress: fix two section mismatch warnings

WARNING: vmlinux.o(.text+0x1bc9c): Section mismatch in reference from the function ct_ca9x4_init_cpu_map() to the function .init.text:scu_get_core_count()
The function ct_ca9x4_init_cpu_map() references
the function __init scu_get_core_count().

WARNING: vmlinux.o(.text+0x1bce8): Section mismatch in reference from the function ct_ca9x4_init_cpu_map() to the function .init.text:set_smp_cross_call()
The function ct_ca9x4_init_cpu_map() references
the function __init set_smp_cross_call().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>