kconfig: use bool instead of boolean for type definition attributes

Linux stopped the use of keyword 'boolean' in Kconfig.

Refer to commit 6341e62b212a2541efb0160c470e90bd226d5496 ("kconfig:
use bool instead of boolean for type definition attributes")
in Linux Kernel.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/cpu/armv7/Kconfig b/arch/arm/cpu/armv7/Kconfig
index bd6108e..41c6639 100644
--- a/arch/arm/cpu/armv7/Kconfig
+++ b/arch/arm/cpu/armv7/Kconfig
@@ -7,14 +7,14 @@
         bool
 
 config ARMV7_NONSEC
-	boolean "Enable support for booting in non-secure mode" if EXPERT
+	bool "Enable support for booting in non-secure mode" if EXPERT
 	depends on CPU_V7_HAS_NONSEC
 	default y
 	---help---
 	Say Y here to enable support for booting in non-secure / SVC mode.
 
 config ARMV7_BOOT_SEC_DEFAULT
-	boolean "Boot in secure mode by default" if EXPERT
+	bool "Boot in secure mode by default" if EXPERT
 	depends on ARMV7_NONSEC
 	default y if TEGRA
 	---help---
@@ -25,14 +25,14 @@
 	variable to "sec" or "nonsec".
 
 config ARMV7_VIRT
-	boolean "Enable support for hardware virtualization" if EXPERT
+	bool "Enable support for hardware virtualization" if EXPERT
 	depends on CPU_V7_HAS_VIRT && ARMV7_NONSEC
 	default y
 	---help---
 	Say Y here to boot in hypervisor (HYP) mode when booting non-secure.
 
 config ARMV7_LPAE
-	boolean "Use LPAE page table format" if EXPERT
+	bool "Use LPAE page table format" if EXPERT
 	depends on CPU_V7
 	default n
 	---help---