package/iozone: update IOZONE_VERSION

Update IOZONE_VERSION to reflect what is used by
https://release-monitoring.org

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit 1e75050bbb9180b2d0861ca10a4c86fd004670dc)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/iozone/iozone.mk

@@ -4,8 +4,8 @@
 #
 ################################################################################
 
-IOZONE_VERSION = 3_490
-IOZONE_SOURCE = iozone$(IOZONE_VERSION).tar
+IOZONE_VERSION = 3.490
+IOZONE_SOURCE = iozone$(subst .,_,$(IOZONE_VERSION)).tar
 IOZONE_SITE = http://www.iozone.org/src/current
 IOZONE_LICENSE = IOzone license (NO DERIVED WORKS ALLOWED)
 # IOzone license details can be found at: