hw/mcu: Remove copy of NXP sdk files

nxp sdk is now external repository.
Local copies are deleted.
Some changes to MK64F12 and MK8xF were made to
used external repository files

.rat-excludes

@@ -165,19 +165,13 @@ clock_config.c
 clock_config.h
 
 # NXP SDK - BSD License.
-nxp-kinetis-sdk
-fsl_clock.c
 MK64FN1M0xxx12_flash.ld
 boot-MK64FN1M0xxx12_flash.ld
 startup_MK64F12.S
 MK82FN256xxx15_flash.ld
 boot-MK82FN256xxx15_flash.ld
 startup_MK82F25615.S
-MK82F25615.h
-MK82F25615_features.h
-system_MK82F25615.h
 system_MK82F25615.c
-fsl_clock.h
 fsl_ftfx_controller.c
 
 # LWIP - BSD License.

LICENSE

@@ -503,10 +503,6 @@ which is available under the "modified Tcl/Tk" license.  Bundled files are:
     * hw/bsp/ublox_bmd_345/split-ublox_bmd_345.ld
     * hw/bsp/ublox_bmd_345/ublox_bmd_345_no_boot.ld
 
-This product bundles part of NXP/FreeScale SDK, which is available
-under the "3-clause BSD" license. Bundled files are:
-    * hw/mcu/nxp/src/ext
-
 This product bundles part of NXP mkw41z, which is available under the
 "3-clause BSD" license.  Bundled files are:
     * hw/mcu/nxp/mkw41z/include/mcu/MKW41Z4.h
@@ -527,13 +523,6 @@ This product bundles part of NXP frdm-k64f, which is available under the
     * hw/bsp/frdm-k64f/src/clock_config.h
     * hw/bsp/frdm-k64f/src/arch/cortex_m4/startup_MK64F12.S
 
-This product bundles part of NXP Kinetis mk64f12, which is available under the
-"3-clause BSD" license.  Bundled files are:
-    * hw/mcu/nxp/kinetis/MK64F12/include/MK64F12.h
-    * hw/mcu/nxp/kinetis/MK64F12/include/MK64F12_features.h
-    * hw/mcu/nxp/kinetis/MK64F12/include/system_MK64F12.h
-    * hw/mcu/nxp/kinetis/MK64F12/src/system_MK64F12.c
-
 This product bundles part of mips architecture and ci40, which is available
 under the "3-clause BSD" license.  Bundled files are:
     * kernel/os/src/arch/mips/asm/ctx.S