powerpc/vdso: Remove DBG()

DBG() is not used anymore. Remove it.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e11a9b50e709f197bb3aa2ed1d80d2dee8714afc.1601197618.git.christophe.leroy@csgroup.eu

arch/powerpc/kernel/vdso.c

@@ -33,14 +33,6 @@
 #include <asm/vdso_datapage.h>
 #include <asm/setup.h>
 
-#undef DEBUG
-
-#ifdef DEBUG
-#define DBG(fmt...) printk(fmt)
-#else
-#define DBG(fmt...)
-#endif
-
 /* The alignment of the vDSO */
 #define VDSO_ALIGNMENT	(1 << 16)