treewide: replace '---help---' in Kconfig files with 'help'

Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

drivers/net/ethernet/xscale/Kconfig

@@ -8,7 +8,7 @@ config NET_VENDOR_XSCALE
 	default y
 	depends on NET_VENDOR_INTEL && (ARM && ARCH_IXP4XX && \
 		   IXP4XX_NPE && IXP4XX_QMGR)
-	---help---
+	help
 	  If you have a network (Ethernet) card belonging to this class, say Y.
 
 	  Note that the answer to this question does not directly affect the
@@ -23,7 +23,7 @@ config IXP4XX_ETH
 	depends on ARM && ARCH_IXP4XX && IXP4XX_NPE && IXP4XX_QMGR
 	select PHYLIB
 	select NET_PTP_CLASSIFY
-	---help---
+	help
 	  Say Y here if you want to use built-in Ethernet ports
 	  on IXP4xx processor.