shim: improve debugging output
shim: improve debugging output

Too often messages flash quickly on the screen and disappear.
Enforce a brief pause after each one, and separate into two
distinct categories: error and debug. The debug ones can be
switched off.

Change-Id: I66d5ef342f5f836eb52bbbcd1174bafe76b5e33a
Signed-off-by: Andrew Boie <aab045b28152628be6af0e556050d0381fd0a34d@intel.com>

CyanogenMod/android_external_uefi_shim,android-ia/platform_external_uefi_shim,CyanogenMod/android_external_uefi_shim,android-ia/platform_external_uefi_shim,android-ia/platform_external_uefi_shim,CyanogenMod/android_external_uefi_shim