Fixed typos and more tutorials

11_exceptions/start.S

@@ -59,8 +59,8 @@ _start:
     movk    x2, #0x30d0, lsl #16
     msr     sctlr_el1, x2
     // set up exception handlers
-    ldr     x1, =_vectors
-    msr     vbar_el1, x1
+    ldr     x2, =_vectors
+    msr     vbar_el1, x2
     // change execution level to EL1
     mov     x2, #0x3c4
     msr     spsr_el2, x2