raw_nand: correct static analysis tool warning

Correct the following warning given by sparse tool:
include/drivers/raw_nand.h:158:3: warning:
 symbol '__packed' was not declared. Should it be static?

Change-Id: I03bd9a8aee5cdc5212ce5225be8033f1a6e92bd9
Signed-off-by: Yann Gautier <yann.gautier@st.com>
1 file changed