This patch fix _eronly value which is used during boot process to initialize
.data section to sram.
Since .data section is 4 byte aligned in flash, also _eronly must follow this
alignment to stay coherent with the start address of .data.
If one of the sections preceeding .data has a size which is not 4 byte aligned,
the _eronly value does not match with .data physical address resulting in wrong
copy of data section to sram and thus an almost immediate hardfault.
Signed-off-by: Federico Braghiroli <federico.braghiroli@gmail.com>