spi_engine: Fixup param ranges and CPHA info (analogdevicesinc#1239)

Set validation ranges for DATA_WIDTH and NUM_OF_CS for the expected
min/max values in the verilog source code.
Also, fix swapped description for CPHA in the documentation.

Signed-off-by: Carlos Oliveira <caosjr8@gmail.com>

Author: caosjr

docs/library/spi_engine/instruction-format.rst

@@ -210,9 +210,9 @@ bus behavior.
        high.
    * - [0]
      - CPHA
-     - Configures the phase of the SCLK signal. When 0, data is updated on the
-       leading edge and sampled on the trailing edge. When 1, data is is
-       sampled on the leading edge and updated on the trailing edge.
+     - Configures the phase of the SCLK signal. When 0, data is sampled on the
+       leading edge and updated on the trailing edge. When 1, data is 
+       sampled on the trailing edge and updated on the leading edge.
 
 .. _spi_engine prescaler-configuration-register:
 

library/spi_engine/spi_engine_execution/spi_engine_execution_ip.tcl

@@ -62,15 +62,15 @@ set cc [ipx::current_core]
 set_property -dict [list \
   "value_validation_type" "range_long" \
   "value_validation_range_minimum" "8" \
-  "value_validation_range_maximum" "256" \
+  "value_validation_range_maximum" "32" \
  ] \
  [ipx::get_user_parameters DATA_WIDTH -of_objects $cc]
 
 ## NUM_OF_CS
 set_property -dict [list \
   "value_validation_type" "range_long" \
   "value_validation_range_minimum" "1" \
-  "value_validation_range_maximum" "32" \
+  "value_validation_range_maximum" "8" \
  ] \
  [ipx::get_user_parameters NUM_OF_CS -of_objects $cc]