mtd: spi: Fix logging in spi-nor-tiny

This fixes dev_xxx() not always being called with a device. In
spi_nor_reg_read, a the slave device may not always be available, so we use
bus and cs instead.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Tested-by: Patrick Delaunay <patrick.delaunay@st.com>
1 file changed