soc/amd/common: Convert to C_ENVIRONMENT_BOOTBLOCK

Add dedicated CAR setup and teardown functions and Kconfig
options to force their inclusion into the build.  The .S files
are mostly duplicated code from the old cache_as_ram.inc file.

The .S files use global proc names in anticipation for use with
the Kconfig symbols C_ENVIRONMENT_BOOTBLOCK and POSTCAR_STAGE.

Move the mainboard romstage functionality into the soc directory
and change the function name to be compatible with the call
from assembly_entry.S.  Drop the BIST check like other devices.

Move InitReset and InitEarly to bootblock.  These AGESA entry
points set some default settings, and release/recapture the
AP cores.  There are currently some early dependencies on
InitReset.  Future work should include:
 * Pull the necessary functionality from InitReset into bootblock
 * Move InitReset and InitEarly to car_stage_entry() and out of
   bootblock
   - Add a mechanism for the BSP to give the APs an address
     to call and skip most of bootblock and verstage (when
     available) (1)
   - Reunify BiosCallOuts.c and OemCustomize.c

(1) During the InitReset call, the BSP enables the APs by setting
    core enable bits in F18F0x1DC and APs begin fetching/executing
    from the reset vector.  The BSP waits for all APs to also
    reach InitReset, where they enter an endless loop.  The BSP
    sends a command to them to execute a HLT instruction and the
    BSP eventually returns from InitReset.  The goal would be to
    preserve this process but prevent APs from rerunning early
    code.

Change-Id: I811c7ef875b980874f3c4b1f234f969ae5618c44
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://review.coreboot.org/19755
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Martin Roth <martinroth@google.com>

src/vendorcode/amd/pi/Makefile.inc

@@ -146,6 +146,7 @@ $(obj)/agesa/libagesa.a: $(call src-to-obj,libagesa,$(agesa_src_files))
 	@printf "    AGESA      $(subst $(obj)/,,$(@))\n"
 	ar rcs $@ $+
 
+bootblock-libs += $(obj)/agesa/libagesa.a
 romstage-libs += $(obj)/agesa/libagesa.a
 ramstage-libs += $(obj)/agesa/libagesa.a