sysctl: add cold_boot sysctl entry

Add a cold_boot parameter which supplements the
boot_reason sysctl entry with information about
whether the system was booted from cold or warm state.

/proc/sys/kernel/cold_boot entry is updated with 1 or 0 when
system was booted from cold or warm boot state respecitively.

CRs-Fixed: 461256
Change-Id: I2bc5d80c8f26eb9e9dbb4b34960d991a51a224e4
Signed-off-by: David Keitel <dkeitel@codeaurora.org>
diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h
index 07209d7..3a2cd22 100644
--- a/arch/arm/include/asm/processor.h
+++ b/arch/arm/include/asm/processor.h
@@ -30,6 +30,7 @@
 #endif
 
 extern unsigned int boot_reason;
+extern unsigned int cold_boot;
 
 struct debug_info {
 #ifdef CONFIG_HAVE_HW_BREAKPOINT