x86, apic: rename 'genapic' to 'apic'

Impact: cleanup

Now that all APIC code is consolidated there's nothing 'gen' about
apics anymore - so rename 'struct genapic' to 'struct apic'.

This shortens the code and is nicer to read as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index c230189..8029369 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -30,7 +30,7 @@
 	void (*smp_read_mpc_oem)(struct mpc_oemtable *oemtable,
 				unsigned short oemsize);
 	int (*setup_ioapic_ids)(void);
-	int (*update_genapic)(void);
+	int (*update_apic)(void);
 };
 
 #endif /* __ASSEMBLY__ */