x86/cpufeatures: Flip the /proc/cpuinfo appearance logic

I'm getting tired of telling people to put a magic "" in the

  #define X86_FEATURE		/* "" ... */

comment to hide the new feature flag from the user-visible
/proc/cpuinfo.

Flip the logic to make it explicit: an explicit "<name>" in the comment
adds the flag to /proc/cpuinfo and otherwise not, by default.

Add the "<name>" of all the existing flags to keep backwards
compatibility with userspace.

There should be no functional changes resulting from this.
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240618113840.24163-1-bp@kernel.org

arch/x86/kernel/cpu/mkcapflags.sh

@@ -30,8 +30,7 @@ dump_array()
 
 		# If the /* comment */ starts with a quote string, grab that.
 		VALUE="$(echo "$i" | sed -n 's@.*/\* *\("[^"]*"\).*\*/@\1@p')"
-		[ -z "$VALUE" ] && VALUE="\"$NAME\""
-		[ "$VALUE" = '""' ] && continue
+		[ ! "$VALUE" ] && continue
 
 		# Name is uppercase, VALUE is all lowercase
 		VALUE="$(echo "$VALUE" | tr A-Z a-z)"