x86/paravirt: Use a single ops structure

Instead of using six globally visible paravirt ops structures combine
them in a single structure, keeping the original structures as
sub-structures.

This avoids the need to assemble struct paravirt_patch_template at
runtime on the stack each time apply_paravirt() is being called (i.e.
when loading a module).

[ tglx: Made the struct and the initializer tabular for readability sake ]

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Cc: virtualization@lists.linux-foundation.org
Cc: akataria@vmware.com
Cc: rusty@rustcorp.com.au
Cc: boris.ostrovsky@oracle.com
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20180828074026.820-9-jgross@suse.com

arch/x86/kernel/cpu/common.c

@@ -1243,7 +1243,7 @@ static void generic_identify(struct cpuinfo_x86 *c)
 # ifdef CONFIG_PARAVIRT
 	do {
 		extern void native_iret(void);
-		if (pv_cpu_ops.iret == native_iret)
+		if (pv_ops.cpu.iret == native_iret)
 			set_cpu_bug(c, X86_BUG_ESPFIX);
 	} while (0);
 # else