Update reference output of tests

Due to recent changes, lots of tests generated a slightly different
error output.

- bank-noexist : This test doesn't generate any error output now as
  unknown labels are left for the linker to resolve.

- null-in-macro : This test used to crash. Now, the parser verifies that
  a MACRO ends in ENDM, generating an error message if not.

Signed-off-by: AntonioND <antonio_nd@outlook.com>

test/asm/bank-noexist.out

@@ -1,2 +0,0 @@
-ERROR:	bank-noexist.asm(2) :
-	'noexist' not defined

test/asm/divzero-instr.out

@@ -1,2 +1,2 @@
-ERROR:	divzero-instr.asm(2) :
+ERROR: divzero-instr.asm(2):
 	division by zero

test/asm/divzero-section-bank.out

@@ -1,2 +1,2 @@
-ERROR:	divzero-section-bank.asm(1) :
+ERROR: divzero-section-bank.asm(1):
 	division by zero

test/asm/macro-@.out

@@ -1,2 +1,2 @@
-ERROR:	macro-@.asm(1) -> @(-1) :
+ERROR: macro-@.asm(1) -> @(-1):
 	Macro '@' not defined

test/asm/null-in-macro.out

@@ -0,0 +1,2 @@
+ERROR: null-in-macro.asm(1):
+	Unterminated MACRO definition

test/asm/undefined-dot.out

@@ -1,2 +1,3 @@
-ERROR:	undefined-dot.asm(3) :
+ERROR: undefined-dot.asm(3):
 	'.' not defined
+../../rgbasm: Assembly aborted in pass 2 (1 errors)!