initial builds of OSK5912 boards need srst_pulls_trst

This is clearly noted in the hardware spec (section 5.2.3); it
works around a chip erratum:  "If the MPU_RESET signal is used,
it may cause the EMIFS bus to lock."

I seem to have a board with such an initial build.  The chip
is labeled XOMAP.  Presumably, parts without that "X" prefix
(eXperimental) resolve this.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

tcl/board/osk5912.cfg

@@ -7,6 +7,10 @@ source [find target/omap5912.cfg]
 # The TI-14 pin needs "trst_only", and J1 connecting 2 & 3.
 reset_config trst_and_srst separate
 
+# NOTE:  boards with XOMAP parts wire nSRST to nPWRON_RESET.
+# That resets everything -- including JTAG and EmbeddedICE.
+# So they must use "reset_config srst_pulls_trst".
+
 # NOTE:  an expansion board could add a trace connector ... if
 # it does, change this appropriately.  And reset_config too,
 # assuming JTAG_DIS reroutes JTAG to that connector.