nb/intel/gm45: Make polling loops more explicit

Replace `while (...);` with `do {} while (...);` so that it's easier to
distinguish polling loops from something else, like function calls. The
`{}` can be understood as "nothing", so that the construct is naturally
read as "do nothing while (...)".

Another reason to prefer this method is that Jenkins does not complain.

Change-Id: Ifbf3cf072f8b817b2fdeece4ef89bae0822bb6e6
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69077
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/northbridge/intel/gm45/pcie.c b/src/northbridge/intel/gm45/pcie.c
index 295bf5b..59a4992 100644
--- a/src/northbridge/intel/gm45/pcie.c
+++ b/src/northbridge/intel/gm45/pcie.c
@@ -33,12 +33,12 @@
 	epbar_write32(EP_PORTARB(7), 0x00005555);
 	epbar_setbits32(EPVC1RCTL, 1 << 16);
 
-	while ((epbar_read8(EPVC1RSTS) & 1) != 0);
+	do {} while ((epbar_read8(EPVC1RSTS) & 1) != 0);
 
 	/* VC1: enable */
 	epbar_setbits32(EPVC1RCTL, 1 << 31);
 
-	while ((epbar_read8(EPVC1RSTS) & 2) != 0);
+	do {} while ((epbar_read8(EPVC1RSTS) & 2) != 0);
 }
 
 /* MCH side */
@@ -56,7 +56,7 @@
 	/* VC1: enable */
 	dmibar_setbits32(DMIVC1RCTL, 1 << 31);
 
-	while ((dmibar_read8(DMIVC1RSTS) & VC1NP) != 0);
+	do {} while ((dmibar_read8(DMIVC1RSTS) & VC1NP) != 0);
 
 	/* additional configuration. */
 	dmibar_setbits32(0x200, 3 << 13);