Fix some commonly made spelling errors in comments.

samples/geos/grc/Makefile

@@ -53,7 +53,7 @@ test.s: test.grc
 	$(GRC) -s test.s test.grc
 
 vlir.cvt: vlir.grc vlir0.s vlir1.s vlir2.s
-# using seperate calls here for demonstration purposes:
+# using separate calls here for demonstration purposes:
 	$(GRC) -t $(SYS) -s vlir.s vlir.grc
 	$(AS) -t $(SYS) vlir.s
 	$(AS) -t $(SYS) vlir0.s
@@ -63,7 +63,7 @@ vlir.cvt: vlir.grc vlir0.s vlir1.s vlir2.s
 
 # you can also do the above in one command:
 #	$(CL) -t $(SYS) -o vlir.cvt vlir.grc vlir0.s vlir1.s vlir2.s
-	
+
 clean:
 	@$(DEL) test.s test.h 2>$(NULLDEV)
 	@$(DEL) vlir.s vlir.cvt vlir.c vlir.h 2>$(NULLDEV)

samples/multidemo.c

@@ -237,7 +237,7 @@ void main (void)
 
         /* The linker makes sure that the call to foo() ends up at the right mem
         ** addr. However it's up to user to make sure that the - right - overlay
-        ** is actually loaded before making the the call.
+        ** is actually loaded before making the call.
         */
         foo ();
     }

samples/overlaydemo.c

@@ -112,7 +112,7 @@ void main (void)
 
         /* The linker makes sure that the call to foo() ends up at the right mem
         ** addr. However it's up to user to make sure that the - right - overlay
-        ** is actually loaded before making the the call.
+        ** is actually loaded before making the call.
         */
         foo ();
     }