flashchips.c: mark IS25LP064 as TEST_OK_PREW

Tested '-w', '-E' and '-r' successfully with
my FT2232H programmer.

Change-Id: I2197ce0be9db7c3d74b24c7445dc06238584ffea
Signed-off-by: Simon Buhrow <simon.buhrow@posteo.de>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/58472
Original-Reviewed-by: Felix Singer <felixsinger@posteo.net>
Original-Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/70979
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/flashchips.c b/flashchips.c
index ec63cf7..9556788 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -7349,7 +7349,7 @@
 		.page_size	= 256,
 		/* OTP: 1024B total; read 0x48; write 0x42 */
 		.feature_bits	= FEATURE_WRSR_WREN | FEATURE_OTP,
-		.tested		= TEST_UNTESTED,
+		.tested		= TEST_OK_PREW,
 		.probe		= probe_spi_rdid,
 		.probe_timing	= TIMING_ZERO,
 		.block_erasers	=