x86: discover_ebda section mismatch

Fix section mismatches.  discover_ebda() can be __init.

WARNING: vmlinux.o(.text+0x738a): Section mismatch: reference to .init.data:ebda_addr (between 'discover_ebda' and 'get_model_name')
WARNING: vmlinux.o(.text+0x73c4): Section mismatch: reference to .init.data:ebda_size (between 'discover_ebda' and 'get_model_name')

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>