kconfig: Remove silentoldconfig from help and docs; fix kconfig/conf's help

As explained by Michal Marek at https://lkml.org/lkml/2011/8/31/189
silentoldconfig has become a misnomer. It has become an internal interface
so remove it from "make help" and Documentation/ to stop confusing people
using it as seen for instance at
https://chromium-review.googlesource.com/835632 Don't remove it from
kconfig/Makefile yet not to break any (other) tool using it.

On the other hand, correct and expand its description in the help of
the (internal) scripts/kconfig/conf.c

Signed-off-by: Marc Herbert <marc.herbert@intel.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index a5ab2f7..cb3ec53 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -34,6 +34,8 @@
 nconfig: $(obj)/nconf
 	$< $(silent) $(Kconfig)
 
+# This has become an internal implementation detail and is now deprecated
+# for external use.
 silentoldconfig: $(obj)/conf
 	$(Q)mkdir -p include/config include/generated
 	$(Q)test -e include/generated/autoksyms.h || \
@@ -144,7 +146,6 @@
 	@echo  '  oldconfig	  - Update current config utilising a provided .config as base'
 	@echo  '  localmodconfig  - Update current config disabling modules not loaded'
 	@echo  '  localyesconfig  - Update current config converting local mods to core'
-	@echo  '  silentoldconfig - Same as oldconfig, but quietly, additionally update deps'
 	@echo  '  defconfig	  - New config with default from ARCH supplied defconfig'
 	@echo  '  savedefconfig   - Save current config as ./defconfig (minimal config)'
 	@echo  '  allnoconfig	  - New config where all options are answered with no'
@@ -153,8 +154,8 @@
 	@echo  '  alldefconfig    - New config with all symbols set to default'
 	@echo  '  randconfig	  - New config with random answer to all options'
 	@echo  '  listnewconfig   - List new options'
-	@echo  '  olddefconfig	  - Same as silentoldconfig but sets new symbols to their'
-	@echo  '                    default value'
+	@echo  '  olddefconfig	  - Same as oldconfig but sets new symbols to their'
+	@echo  '                    default value without prompting'
 	@echo  '  kvmconfig	  - Enable additional options for kvm guest kernel support'
 	@echo  '  xenconfig       - Enable additional options for xen dom0 and guest kernel support'
 	@echo  '  tinyconfig	  - Configure the tiniest possible kernel'
diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index a8a97ef..307bc3f 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -484,8 +484,9 @@ static void conf_usage(const char *progname)
 	printf("  --listnewconfig         List new options\n");
 	printf("  --oldaskconfig          Start a new configuration using a line-oriented program\n");
 	printf("  --oldconfig             Update a configuration using a provided .config as base\n");
-	printf("  --silentoldconfig       Same as oldconfig, but quietly, additionally update deps\n");
-	printf("  --olddefconfig          Same as silentoldconfig but sets new symbols to their default value\n");
+	printf("  --silentoldconfig       Similar to oldconfig but generates configuration in\n"
+	       "                          include/{generated/,config/} (oldconfig used to be more verbose)\n");
+	printf("  --olddefconfig          Same as oldconfig but sets new symbols to their default value\n");
 	printf("  --oldnoconfig           An alias of olddefconfig\n");
 	printf("  --defconfig <file>      New config with default defined in <file>\n");
 	printf("  --savedefconfig <file>  Save the minimal current configuration to <file>\n");