[ARM] 3792/2: Fix description of ZBOOT_ROM_BSS

The documentation for the ZBOOT_ROM_BSS config option describes it as
"The base address of 64KiB of read/write memory in the target for the
ROM-able zImage..." In actuality, it requires more than 100 KiB of
space in addition to enough space to hold the decompressed kernel.
This patch fixes the description in the Kconfig file.
Signed-off-by: NDan Fandrich <dfandrich@intrinsyc.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/Kconfig

@@ -652,11 +652,12 @@ config ZBOOT_ROM_BSS
 	hex "Compressed ROM boot loader BSS address"
 	default "0"
 	help
-	  The base address of 64KiB of read/write memory in the target
-	  for the ROM-able zImage, which must be available while the
-	  decompressor is running.  Platforms which normally make use of
-	  ROM-able zImage formats normally set this to a suitable
-	  value in their defconfig file.
+	  The base address of an area of read/write memory in the target
+	  for the ROM-able zImage which must be available while the
+	  decompressor is running. It must be large enough to hold the
+	  entire decompressed kernel plus an additional 128 KiB.
+	  Platforms which normally make use of ROM-able zImage formats
+	  normally set this to a suitable value in their defconfig file.
 
 	  If ZBOOT_ROM is not enabled, this has no effect.