feat(rpi4): add PCI SMCCC build variant to CI

The RaspberryPi 4 build can include support for the PCIe SMCCC
interface, add this option to the CI build to increase coverage.
The option only adds code to the build, so we do not need to build
the standard variant anymore to cover everything.

Change-Id: I1c8030cd8bf2c79a7559ad352b2fd2d4a23b4ce3
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/script/tf-coverity/tf-cov-make b/script/tf-coverity/tf-cov-make
index 04f6a18..e82a0c7 100755
--- a/script/tf-coverity/tf-cov-make
+++ b/script/tf-coverity/tf-cov-make
@@ -518,7 +518,7 @@
 # Raspberry Pi Platforms
 make PLAT=rpi3 $(common_flags) ${TBB_OPTIONS} \
     ENABLE_STACK_PROTECTOR=strong PRELOADED_BL33_BASE=0xDEADBEEF all
-make PLAT=rpi4 $(common_flags) all
+clean_build PLAT=rpi4 $(common_flags) SMC_PCI_SUPPORT=1 all
 
 # Cannot use $(common_flags) for LS1043 platform, as then
 # the binaries do not fit in memory.