rtla: Check pkg-config install

JIRA: https://issues.redhat.com/browse/RHEL-117873

commit 7b128f1
Author: Tao Chen <chen.dylane@linux.dev>
Date:   Fri Aug 8 12:05:27 2025 +0800

    rtla: Check pkg-config install

    The tool pkg-config used to check libtraceevent and libtracefs, if not
    installed, it will report the libs not found, even though they have
    already been installed.

    Before:
    libtraceevent is missing. Please install libtraceevent-dev/libtraceevent-devel
    libtracefs is missing. Please install libtracefs-dev/libtracefs-devel

    After:
    Makefile.config:10: *** Error: pkg-config needed by libtraceevent/libtracefs is missing
    on this system, please install it.

    Link: https://lore.kernel.org/20250808040527.2036023-2-chen.dylane@linux.dev
    Fixes: 01474dc ("tools/rtla: Use tools/build makefiles to build rtla")
    Signed-off-by: Tao Chen <chen.dylane@linux.dev>
    Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

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

Author: lenticularis39

tools/tracing/rtla/Makefile.config

@@ -1,10 +1,18 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
+include $(srctree)/tools/scripts/utilities.mak
+
 STOP_ERROR :=
 
 LIBTRACEEVENT_MIN_VERSION = 1.5
 LIBTRACEFS_MIN_VERSION = 1.6
 
+ifndef ($(NO_LIBTRACEEVENT),1)
+  ifeq ($(call get-executable,$(PKG_CONFIG)),)
+    $(error Error: $(PKG_CONFIG) needed by libtraceevent/libtracefs is missing on this system, please install it)
+  endif
+endif
+
 define lib_setup
   $(eval LIB_INCLUDES += $(shell sh -c "$(PKG_CONFIG) --cflags lib$(1)"))
   $(eval LDFLAGS += $(shell sh -c "$(PKG_CONFIG) --libs-only-L lib$(1)"))