[PATCH] nvmem: include linux/err.h from header

[Arnd Bergmann <arnd@arndb.de>]

The new support for nvmem devices from the rtc layer caused a build
error in some configurations:

include/linux/nvmem-provider.h: In function 'nvmem_register':
include/linux/nvmem-provider.h:51:9: error: implicit declaration of function 'ERR_PTR' [-Werror=implicit-function-declaration]

This adds the missing include to ensure we can always include
the header.

Fixes: 697e5a47aa12 ("rtc: add generic nvmem support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
I'd suggest adding this patch in the rtc tree on top of the
nvmem support there.
---
 include/linux/nvmem-provider.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index cd93416d762e..497706f5adca 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -12,6 +12,9 @@
 #ifndef _LINUX_NVMEM_PROVIDER_H
 #define _LINUX_NVMEM_PROVIDER_H
 
+#include <linux/err.h>
+#include <linux/errno.h>
+
 struct nvmem_device;
 struct nvmem_cell_info;
 typedef int (*nvmem_reg_read_t)(void *priv, unsigned int offset,
-- 
2.9.0