ACPI: Move definition of PREFIX from acpi_bus.h to internal..h

Linux/ACPI core files using internal.h all PREFIX "ACPI: ",
however, not all ACPI drivers use/want it -- and they
should not have to #undef PREFIX to define their own.

Add GPL commment to internal.h while we are there.

This does not change any actual console output,
asside from a whitespace fix.

Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/fan.c b/drivers/acpi/fan.c
index 53698ea..f419849 100644
--- a/drivers/acpi/fan.c
+++ b/drivers/acpi/fan.c
@@ -34,6 +34,8 @@
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
 
+#define PREFIX "ACPI: "
+
 #define ACPI_FAN_CLASS			"fan"
 #define ACPI_FAN_FILE_STATE		"state"