x86/cpuid: Drop special_features[]

While the ! annotation is useful to indicate that something special is
happening, an array of bits is not.  Drop it, to prevent mistakes.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 69e1472d21)

x86/cpuid: Half revert "x86/cpuid: Drop special_features[]"

xen-cpuid does print out the list of special features, and this is helpful to
keep.

Fixes: 69e1472d21 ("x86/cpuid: Drop special_features[]")
Reported-by: Jan Beulich <JBeulich@suse.com>
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 0ba0663b1b)

xen/arch/x86/cpuid.c

@@ -14,7 +14,6 @@
 #include <asm/xstate.h>
 
 const uint32_t known_features[] = INIT_KNOWN_FEATURES;
-const uint32_t special_features[] = INIT_SPECIAL_FEATURES;
 
 static const uint32_t pv_max_featuremask[] = INIT_PV_MAX_FEATURES;
 static const uint32_t hvm_shadow_max_featuremask[] = INIT_HVM_SHADOW_MAX_FEATURES;
@@ -1133,7 +1132,6 @@ void guest_cpuid(const struct vcpu *v, uint32_t leaf,
 static void __init __maybe_unused build_assertions(void)
 {
     BUILD_BUG_ON(ARRAY_SIZE(known_features) != FSCAPINTS);
-    BUILD_BUG_ON(ARRAY_SIZE(special_features) != FSCAPINTS);
     BUILD_BUG_ON(ARRAY_SIZE(pv_max_featuremask) != FSCAPINTS);
     BUILD_BUG_ON(ARRAY_SIZE(hvm_shadow_max_featuremask) != FSCAPINTS);
     BUILD_BUG_ON(ARRAY_SIZE(hvm_hap_max_featuremask) != FSCAPINTS);

xen/include/asm-x86/cpuid.h

@@ -14,7 +14,6 @@
 #include <public/sysctl.h>
 
 extern const uint32_t known_features[FSCAPINTS];
-extern const uint32_t special_features[FSCAPINTS];
 
 void init_guest_cpuid(void);