tools: PCI: Remove unused BILLION macro

The macro BILLION is never referenced in the code.  Remove it.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: zhang jiao <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Signed-off-by: Krzysztof Wilczyński <[email protected]>

Author: zhang jiao

tools/pci/pcitest.c

@@ -16,8 +16,6 @@
 
 #include <linux/pcitest.h>
 
-#define BILLION 1E9
-
 static char *result[] = { "NOT OKAY", "OKAY" };
 static char *irq[] = { "LEGACY", "MSI", "MSI-X" };