kernel: init.c: Added required hooks for the relocation

This patch splits the text section into 2 parts. The first section
will have some info regarding vector tables and debug info. The
second section will have the complete text section.
This is needed to force the required functions and data variables
the correct locations.
This is due to the behavior of the linker. The linker will only link
once and hence this text section had to be split to make room
for the generated linker script.

Added a new Kconfig CODE_DATA_RELOCATION which when enabled will
invoke the script, which does the required relocation.

Added hooks inside init.c for bss zeroing and data copy operations.
Needed when we have to copy data from ROM to required memory type.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>