gallium/hud: fix rounding error in nic bps computation

While at it, fix typo in "rounding error" :P

Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
15 jobs for !479 with coverity-fixes in 11 minutes and 7 seconds (queued for 2 minutes and 5 seconds)
detached
Status Job ID Name Coverage
  Containers Build
passed #213977
ubuntu

00:00:23

 
  Build+Test
passed #213978
autotools

00:10:43

passed #213980
meson-clang

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passed #213986
meson-gallium-clover-llvm

00:05:59

passed #213987
meson-gallium-clover-llvm39

00:01:48

passed #213985
meson-gallium-drivers-other

00:04:47

passed #213984
meson-gallium-radeonsi

00:04:48

passed #213988
meson-gallium-st-other

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passed #213979
meson-gallium-swr

00:09:06

passed #213983
meson-glvnd

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passed #213982
meson-loader-classic-dri

00:01:58

passed #213981
meson-vulkan

00:01:54

passed #213990
scons-llvm

00:03:50

passed #213989
scons-nollvm

00:05:04

passed #213991
scons-swr

00:04:29