Include external ram section in the linker template to process it
through linker script generation mechanism. This enables redirection of .bss section to external memory using linker fragments
libnet80211, libpp, libbt, liblwip: Redirect .bss through fragments
* Prevents section type conflict errors if (say) const & non-const data
is put into the same section (ie with DRAM_ATTR)
* Allows linker --gc-sections to remove unused custom sections