soc/amd: move bootblock inside main SoC directories

There's no need to have the bootblock in its own sub-directory, so move
it to each SoC's main directory to avoid clutter. This makes soc/amd
more consistent with the coreboot code base in src/northbridge,
src/southbridge and src/soc with the exception of src/soc/intel.

Change-Id: I78a9ce1cd0d790250a66c82bb1d8aa6c3b4f7162
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47982
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/picasso/Makefile.inc

@@ -11,7 +11,7 @@ subdirs-y += ../../../cpu/x86/pae
 subdirs-y += ../../../cpu/x86/smm
 subdirs-$(CONFIG_VBOOT_STARTS_BEFORE_BOOTBLOCK) += psp_verstage
 
-bootblock-y += bootblock/bootblock.c
+bootblock-y += bootblock.c
 bootblock-y += aoac.c
 bootblock-y += southbridge.c
 bootblock-y += i2c.c

src/soc/amd/stoneyridge/Makefile.inc

@@ -12,7 +12,7 @@ subdirs-y += ../../../cpu/x86/smm
 
 bootblock-$(CONFIG_STONEYRIDGE_UART) += uart.c
 bootblock-y += BiosCallOuts.c
-bootblock-y += bootblock/bootblock.c
+bootblock-y += bootblock.c
 bootblock-y += gpio.c
 bootblock-y += i2c.c
 bootblock-y += enable_usbdebug.c