README.md: shift description of kernel config files

Document it in sys/README.md instead. Describe the purpose of LINT
config files as well.

Reviewed by:	imp
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D37134

Author: mhorne

README.md

@@ -33,7 +33,6 @@ Source Roadmap:
 | share | Shared resources. |
 | stand | Boot loader sources. |
 | sys | Kernel sources (see [sys/README.md](sys/README.md)). |
-| sys/`arch`/conf | Kernel configuration files. GENERIC is the configuration used in release builds. NOTES contains documentation of all possible entries. |
 | tests | Regression tests which can be run by Kyua.  See [tests/README](tests/README) for additional information. |
 | tools | Utilities for regression testing and miscellaneous tasks. |
 | usr.bin | User commands. |

sys/README.md

@@ -4,6 +4,11 @@ FreeBSD Kernel Source:
 This directory contains the source files and build glue that make up the FreeBSD
 kernel and its modules, including both original and contributed software.
 
+Kernel configuration files are located in the `conf/` subdirectory of each
+architecture. `GENERIC` is the configuration used in release builds. `NOTES`
+contains documentation of all possible entries. `LINT` is a compile-only
+configuration used to maximize build coverage and detect regressions.
+
 Source Roadmap:
 ---------------
 | Directory | Description |