Revert "eina debug - fix segv if an app is compiled with -pg for profiling"

This reverts commit 8343de6ce3.

This borke mac os build, CI is spamming on irc channels and addtional
tests are failing. I would give this back to the drawingboard.

ref T7029

Differential Revision: https://phab.enlightenment.org/D6310

src/lib/eina/eina_debug_bt.c

@@ -37,12 +37,7 @@
 
 #ifndef _WIN32
 # include <signal.h>
-// realtime signals guarantee a minimum of 8, so SIGRTMIN + 7 would be valid
-// at a minimum, so let's choose + 6 ... second last of the minimum set.
-// SIGRTMAX of course is defined too... note the manual pages for sigation say
-// that it calls rt_sigaction transparently for us so... no need for anything
-// else special
-# define SIG (SIGRTMIN + 6)
+# define SIG SIGPROF
 #endif
 
 static Eina_Semaphore _wait_for_bts_sem;