oci8 php5.6 fix dtrace

oci8_dtrace.txt

I fix this problem in my CENTOS 6.6 and php 5.6.8 in these two ways:

- If you need DTRACE:

yum install systemtap-sdt-devel
export PHP_DTRACE=yes
pecl install oci8

- if you don't like DTRACE:

Download the oci8 tar ball and extract the files
modify the file 'php_oci8_int.h', change the 48th line 
#include "oci8_dtrace_gen.h" to #undef HAVE_OCI8_DTRACE
phpize
./configure --with-oci8=
make
make install