tau_exec interferes with PAPI ROCm component

[gcongiu]

The following line seems problematic when TAU and PAPI are installed through Spack (Spack installed PAPI always uses HSA_TOOLS_LIB to locate librocprofiler64.so):

tau2/tools/src/tau_exec

Line 1326 in 8bfe9aa

$dryrun export HSA_TOOLS_LIB=$TAU_HSA_TOOLS_LIB

:

When I run tau_exec with PAPI + ROCm component support enabled, the component in PAPI is always disabled. This appears to be related to the line above, that sets HSA_TOOLS_LIB="" even though the "-rocm" option is not used.

Perhaps this should be changed to:

$dryrun [ "x$TAU_HSA_TOOLS_LIB" != "x" ] && export HSA_TOOLS_LIB=TAU_HSA_TOOLS_LIB

instead? Perhaps even prevent tau_exec from setting HSA_TOOLS_LIB if already set?