Fixup example linker scripts to add VECTOR region.

Author: jonathanpallant

examples/mps3-an536/memory.x

@@ -9,5 +9,6 @@ MEMORY {
     DDR  : ORIGIN = 0x20000000, LENGTH = 128M
 }
 
+REGION_ALIAS("VECTORS", QSPI);
 REGION_ALIAS("CODE", QSPI);
 REGION_ALIAS("DATA", DDR);

examples/versatileab/memory.x

@@ -8,5 +8,6 @@ MEMORY {
     SDRAM : ORIGIN = 0, LENGTH = 128M
 }
 
+REGION_ALIAS("VECTORS", SDRAM);
 REGION_ALIAS("CODE", SDRAM);
 REGION_ALIAS("DATA", SDRAM);