linux sparc compile issue

Hi,

while doing regular builds via buildroot autobuilders
a compile problem for sparc 32bit v8 was found.
It seems the defines for Linux are other than for Solaris.

Following patch fixes it for buildroot:

The gcc predefines for Linux are __sparc_v8__/__sparc_v7__

Signed-off-by: Waldemar Brodkorb <wbx(at)openadk(dot)org>

diff -Nur postgresql-9.4.4.orig/src/include/storage/s_lock.h postgresql-9.4.4/src/include/storage/s_lock.h
--- postgresql-9.4.4.orig/src/include/storage/s_lock.h 2015-06-09 21:29:38.000000000 +0200
+++ postgresql-9.4.4/src/include/storage/s_lock.h 2015-08-09 19:57:06.000000000 +0200
@@ -420,12 +420,12 @@
: "=r"(_res), "+m"(*lock)
: "r"(lock)
: "memory");
-#if defined(__sparcv7)
+#if defined(__sparcv7) || defined(__sparc_v7__)
/*
* No stbar or membar available, luckily no actually produced hardware
* requires a barrier.
*/
-#elif defined(__sparcv8)
+#elif defined(__sparcv8) || defined(__sparc_v8__)
/* stbar is available (and required for both PSO, RMO), membar isn't */
__asm__ __volatile__ ("stbar \n":::"memory");
#else
@@ -438,13 +438,13 @@
return (int) _res;
}

-#if defined(__sparcv7)
+#if defined(__sparcv7) || defined(__sparc_v7__)
/*
* No stbar or membar available, luckily no actually produced hardware
* requires a barrier.
*/
#define S_UNLOCK(lock) (*((volatile slock_t *) (lock)) = 0)
-#elif defined(__sparcv8)
+#elif defined(__sparcv8) || defined(__sparc_v8__)
/* stbar is available (and required for both PSO, RMO), membar isn't */
#define S_UNLOCK(lock) \
do \