redhat/kernel.spec.template: Link rtla against in-tree libcpupower

JIRA: https://issues.redhat.com/browse/RHEL-40744
Upstream Status: RHEL only

To build rtla with --deepest-idle-state support, it requires cpuidle.h
and libcpupower to be present. Pass necessary LDFLAGS and INCLUDES to
make the rtla build find in-tree libcpupower that is built before rtla.

If not on %{cpupowerarchs}, built rtla without libcpupower support.

Signed-off-by: Tomas Glozar <tglozar@redhat.com>

Author: lenticularis39

redhat/kernel.spec.template

@@ -3106,6 +3106,13 @@ chmod +x tools/perf/check-headers.sh
 %global tools_make \
   CFLAGS="${RPM_OPT_FLAGS}" LDFLAGS="%{__global_ldflags}" EXTRA_CFLAGS="${RPM_OPT_FLAGS}" %{make} %{?make_opts}
 
+%ifarch %{cpupowerarchs}
+    # link against in-tree libcpupower for idle state support
+    %global rtla_make %{tools_make} LDFLAGS="%{__global_ldflags} -L../../power/cpupower" INCLUDES="-I../../power/cpupower/lib"
+%else
+    %global rtla_make %{tools_make}
+%endif
+
 %if %{with_tools}
 %ifarch %{cpupowerarchs}
 # cpupower
@@ -3165,7 +3172,7 @@ pushd tools/verification/rv/
 popd
 pushd tools/tracing/rtla
 %{log_msg "build rtla"}
-%{tools_make}
+%{rtla_make}
 popd
 %endif