ARM: 9213/1: Print message about disabled Spectre workarounds only once

Print the message about disabled Spectre workarounds only once. The
message is printed each time CPU goes out from idling state on NVIDIA
Tegra boards, causing storm in KMSG that makes system unusable.

Cc: [e-mail]
Signed-off-by: Dmitry Osipenko <[e-mail]>
Signed-off-by: Russell King (Oracle) <[e-mail]>

arch/arm/mm/proc-v7-bugs.c

···
 #else
 static unsigned int spectre_v2_install_workaround(unsigned int method)
 {
-	pr_info("CPU%u: Spectre V2: workarounds disabled by configuration\n",
-		smp_processor_id());
+	pr_info_once("Spectre V2: workarounds disabled by configuration\n");
 
 	return SPECTRE_VULNERABLE;
 }