feat(io_mtd): offset management for FIP usage

A new seek handler is also created. It will be used for NAND to add an
extra offset in case of bad blocks, when FIP is used.

Change-Id: I03fb1588b44029db50583c0b2e7af7a1e88a5a7a
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
2 files changed