BUG #15648: oracle_fdw extension not able to create

The following bug has been logged on the website:

Bug reference: 15648
Logged by: ramakrishnan r
Email address: prakash(dot)ramakrishnan(dot)ap(at)nielsen(dot)com
PostgreSQL version: 11.1
Operating system: rhel 7.4
Description:

Hi Team,

we are not able to create the extesnion oracle_fdw and we did pre check for
oracle client 12c and getting below error.
==> cat /etc/redhat-
cat: /etc/redhat-: No such file or directory
postgres(at)brurhenppp001(dot)enterprisenet(dot)org:/home/postgres/software/oracle_fdw-2.1.0
==> cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.5 (Maipo)
postgres(at)brurhenppp001(dot)enterprisenet(dot)org:/home/postgres/software/oracle_fdw-2.1.0
==> ll
total 984
-rw-r--r--. 1 postgres postgres 15887 Sep 25 12:04 CHANGELOG
drwxr-xr-x. 2 postgres postgres 123 Sep 25 12:04 expected
-rw-r--r--. 1 postgres postgres 1086 Sep 25 12:04 LICENSE
-rw-r--r--. 1 postgres postgres 1968 Sep 25 12:04 Makefile
-rw-r--r--. 1 postgres postgres 1459 Sep 25 12:17 META.json
drwxr-xr-x. 2 postgres postgres 99 Sep 25 12:04 msvc
-rw-r--r--. 1 postgres postgres 231 Sep 25 12:04
oracle_fdw--1.0--1.1.sql
-rw-r--r--. 1 postgres postgres 1003 Sep 25 12:04 oracle_fdw--1.1.sql
-rw-r--r--. 1 postgres postgres 194018 Sep 25 12:04 oracle_fdw.c
-rw-r--r--. 1 postgres postgres 133 Sep 25 12:04 oracle_fdw.control
-rw-r--r--. 1 postgres postgres 8284 Sep 25 12:04 oracle_fdw.h
-rw-------. 1 postgres postgres 570584 Feb 15 16:46 oracle_fdw.o
-rw-r--r--. 1 postgres postgres 44474 Sep 25 12:04 oracle_gis.c
-rw-r--r--. 1 postgres postgres 93976 Sep 25 12:04 oracle_utils.c
-rw-r--r--. 1 postgres postgres 37530 Sep 25 12:04 README.oracle_fdw
drwxr-xr-x. 2 postgres postgres 98 Sep 25 12:04 sql
-rw-r--r--. 1 postgres postgres 315 Sep 25 12:04 TODO
postgres(at)brurhenppp001(dot)enterprisenet(dot)org:/home/postgres/software/oracle_fdw-2.1.0
==> make
gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement
-Wendif-labels -Wmissing-format-attribute -Wformat-security
-fno-strict-aliasing -fwrapv -fexcess-precision=standard -O2 -g -pipe -Wall
-Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong
--param=ssp-buffer-size=4 -grecord-gcc-switches -m64 -mtune=generic -fPIC
-I/sdk/include -I/oci/include -I/rdbms/public
-I/usr/include/oracle/12.2/client -I/usr/include/oracle/12.2/client64
-I/usr/include/oracle/12.1/client -I/usr/include/oracle/12.1/client64
-I/usr/include/oracle/11.2/client -I/usr/include/oracle/11.2/client64
-I/usr/include/oracle/11.1/client -I/usr/include/oracle/11.1/client64
-I/usr/include/oracle/10.2.0.5/client
-I/usr/include/oracle/10.2.0.5/client64
-I/usr/include/oracle/10.2.0.4/client
-I/usr/include/oracle/10.2.0.4/client64
-I/usr/include/oracle/10.2.0.3/client
-I/usr/include/oracle/10.2.0.3/client64 -I. -I./
-I/usr/pgsql-11/include/server -I/usr/pgsql-11/include/internal
-D_GNU_SOURCE -I/usr/include/libxml2 -I/usr/include -c -o oracle_utils.o
oracle_utils.c
oracle_utils.c:22:17: fatal error: oci.h: No such file or directory
#include <oci.h>
^
compilation terminated.
make: *** [oracle_utils.o] Error 1
postgres(at)brurhenppp001(dot)enterprisenet(dot)org:/home/postgres/software/oracle_fdw-2.1.0