honeybuns: enable updates over USB-PD

Enable the RSA verification of the RW partition,
so we are using the RW partition by default and
the USB PD flashing VDMs are able to update
the firmware over the Control Channel.

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>

BRANCH=samus
BUG=chrome-os-partner:47823
TEST=run the following sequence on a Samus connected to Honeybuns :
ectool --name=cros_pd infopddev 1
ectool --name=cros_pd flashpd 5 1 ec.RW.bin
ectool --name=cros_pd version
and see the honeybuns properly updated and running the new version.

Change-Id: I8f1612ee153a412620bae5822d1b354ad8072916
Reviewed-on: https://chromium-review.googlesource.com/312998
Commit-Ready: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>

board/honeybuns/board.h

@@ -21,6 +21,8 @@
 #define CONFIG_I2C
 #define CONFIG_I2C_MASTER
 #undef CONFIG_LID_SWITCH
+#define CONFIG_RSA
+#define CONFIG_RWSIG
 #define CONFIG_SHA256
 #define CONFIG_STM_HWTIMER32
 #undef CONFIG_TASK_PROFILING

board/honeybuns/dev_key.pem

@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----