Merged in masayuki2009/nuttx.nuttx/lc823450 (pull request #531)

lc823450-xgevk audio support

* arch/arm/src/lc823450: Add IPL2 support

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* configs/lc823450-xgevk: Add IPL2 support

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* libc/audio: Fix compilation error in lib_buffer.c

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* drivers/audio: Add WM8774 support

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* arch/arm/src/lc823450: Add I2S support

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

* configs/lc823450-xgevk: Add WM8774 support

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

Approved-by: Gregory Nutt <gnutt@nuttx.org>