x86/build: restrict contents of asm-offsets.h when !HVM / !PV

This file has a long dependencies list (through asm-offsets.[cs]) and a
long list of dependents. IOW if any of the former changes, all of the
latter will be rebuilt, even if there's no actual change to the
generated file. Therefore avoid producing symbols we don't actually
need, depending on configuration.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>

xen/arch/x86/x86_64/asm-offsets.c

@@ -84,6 +84,7 @@ void __dummy__(void)
     DEFINE(_VGCF_syscall_disables_events,  _VGCF_syscall_disables_events);
     BLANK();
 
+#ifdef CONFIG_HVM
     OFFSET(VCPU_svm_vmcb_pa, struct vcpu, arch.hvm.svm.vmcb_pa);
     OFFSET(VCPU_svm_vmcb, struct vcpu, arch.hvm.svm.vmcb);
     BLANK();
@@ -99,6 +100,7 @@ void __dummy__(void)
     OFFSET(VCPU_nhvm_p2m, struct vcpu, arch.hvm.nvcpu.nv_p2m);
     OFFSET(VCPU_nsvm_hap_enabled, struct vcpu, arch.hvm.nvcpu.u.nsvm.ns_hap_enabled);
     BLANK();
+#endif
 
 #ifdef CONFIG_PV
     OFFSET(DOMAIN_is_32bit_pv, struct domain, arch.pv.is_32bit);
@@ -128,6 +130,7 @@ void __dummy__(void)
     DEFINE(CPUINFO_sizeof, sizeof(struct cpu_info));
     BLANK();
 
+#ifdef CONFIG_PV
     OFFSET(TRAPINFO_eip, struct trap_info, address);
     OFFSET(TRAPINFO_cs, struct trap_info, cs);
     OFFSET(TRAPINFO_flags, struct trap_info, flags);
@@ -139,6 +142,7 @@ void __dummy__(void)
     OFFSET(TRAPBOUNCE_cs, struct trap_bounce, cs);
     OFFSET(TRAPBOUNCE_eip, struct trap_bounce, eip);
     BLANK();
+#endif
 
     OFFSET(VCPUMSR_spec_ctrl_raw, struct vcpu_msrs, spec_ctrl.raw);
     BLANK();