flashchips: Mark Eon EN25S40 as tested

As reported by `The_Raven Raven` on the mailing list.

Change-Id: I00f9c6fcf13c486765d0ac4fe06a8b0989b03f91
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/28811
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/flashchips.c b/flashchips.c
index aab0870..aa5d9bf 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -5091,7 +5091,7 @@
 		.page_size	= 256,
 		/* OTP: 256B total; enter 0x3A */
 		.feature_bits	= FEATURE_WRSR_WREN | FEATURE_OTP,
-		.tested		= TEST_UNTESTED,
+		.tested		= TEST_OK_PREW,
 		.probe		= probe_spi_rdid,
 		.probe_timing	= TIMING_ZERO,
 		.block_erasers	= {