linker-tool-gcc: revise for MMU support

We need to do a few things differently if we are to support
a virtual memory map, i.e. CONFIG_MMU where CONFIG_KERNEL_VM_BASE
is not the same as CONFIG_SRAM_BASE_ADDRESS.

 - All sections must be specified with a VMA and LMA, where
   VMA is the virtual address and LMA is the physical memory
   location.
 - All sections must be specified with ALIGN_WITH_INPUT to
   keep VMAs and LMAs synchronized

To do this, the existing linker macros need some adjustment:

 - GROUP_LINK_IN undefined when CONFIG_KERNEL_VM_BASE is not
   the same as CONFIG_SRAM_BASE_ADDRESS.
 - New macro GROUP_ROM_LINK_IN for text/rodata sections
 - New macro GROUP_NOLOAD_LINK_IN for bss/noinit sections
 - Implicit ALIGN_WITH_INPUT for all sections

GROUP_FOLLOWS_AT is unused anywhere in the kernel for years
now and has been removed.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>