Fix gdb scripts [scripts]

Newer gdb versions have introduced the 'define-prefix' command making
'def' ambiguous, use 'define' instead.

Set the watchdog flag before reseting the lpc1769 microcontroller to
avoid entering the rom bootloader.

Fix svd path assuming that gdb is executed from the nuttx directory.

scripts/gdb/gdbinit

@@ -1,23 +1,24 @@
-def rst
+define rst
+	set *((uint32_t*) 0x40000000) = 1 << 2
 	monitor reset halt
 end
 
-def start_timer
+define start_timer
 	set *(unsigned int*)0xE000EDFC |= 0x01000000
 	set *(unsigned int*)0xE0001004 = 0
 	set *(unsigned int*)0xE0001000 = 1
 end
 
-def read_timer
+define read_timer
 	p *(unsigned int*)0xE0001004
 end
 
-def ldr
+define ldr
 	load
 	rst
 end
 
-def ldrc
+define ldrc
 	load
 	rst
 	c

scripts/gdb/pygdbinit

@@ -1,23 +1,24 @@
-def rst
+define rst
+	set *((uint32_t*) 0x40000000) = 1 << 2
 	monitor reset halt
 end
 
-def start_timer
+define start_timer
 	set *(unsigned int*)0xE000EDFC |= 0x01000000
 	set *(unsigned int*)0xE0001004 = 0
 	set *(unsigned int*)0xE0001000 = 1
 end
 
-def read_timer
+define read_timer
 	p *(unsigned int*)0xE0001004
 end
 
-def ldr
+define ldr
 	load
 	rst
 end
 
-def ldrc
+define ldrc
 	load
 	rst
 	c
@@ -34,5 +35,5 @@ LoadSVD()
 
 end
 
-svd_load ./scripts/gdb/LPC176x5x_v0.2.svd
+svd_load ../scripts/gdb/LPC176x5x_v0.2.svd