KVM: arm64: Replace ternary flags with str_on_off() helper

Replace repetitive ternary expressions with the str_on_off() helper
function. This change improves code readability and ensures consistency
in tracepoint string formatting

Signed-off-by: Seongsu Park <[e-mail]>
Reviewed-by: Zenghui Yu <[e-mail]>
Reviewed-by: Anshuman Khandual <[e-mail]>
Link: https://lore.kernel.org/r/1891546521.01744691102904.JavaMail.epsvc@epcpadp1new
Signed-off-by: Marc Zyngier <[e-mail]>

arch/arm64/kvm/trace_arm.h

···
 	    ),
 
 	    TP_printk("S/W flush at 0x%016lx (cache %s)",
-		      __entry->vcpu_pc, __entry->cache ? "on" : "off")
+		      __entry->vcpu_pc, str_on_off(__entry->cache))
 );
 
 TRACE_EVENT(kvm_toggle_cache,
···
 	    ),
 
 	    TP_printk("VM op at 0x%016lx (cache was %s, now %s)",
-		      __entry->vcpu_pc, __entry->was ? "on" : "off",
-		      __entry->now ? "on" : "off")
+		      __entry->vcpu_pc, str_on_off(__entry->was),
+		      str_on_off(__entry->now))
 );
 
 /*