configure: default configure log to config.log

this is consistent with autoconf

Change-Id: I1860831693789259ee35d644775653d6a460cc77

.gitignore

@@ -16,7 +16,7 @@
 /.install-*
 /.libs
 /Makefile
-/config.err
+/config.log
 /config.mk
 /decode_to_md5
 /decode_to_md5.c

README

@@ -97,7 +97,7 @@ COMPILING THE APPLICATIONS/LIBRARIES:
 
   5. Configuration errors
   If the configuration step fails, the first step is to look in the error log.
-  This defaults to config.err. This should give a good indication of what went
+  This defaults to config.log. This should give a good indication of what went
   wrong. If not, contact us for support.
 
 SUPPORT

build/make/configure.sh

@@ -75,7 +75,7 @@ Options:
 
 Build options:
   --help                      print this message
-  --log=yes|no|FILE           file configure log is written to [config.err]
+  --log=yes|no|FILE           file configure log is written to [config.log]
   --target=TARGET             target platform tuple [generic-gnu]
   --cpu=CPU                   optimize for a specific cpu rather than a family
   --extra-cflags=ECFLAGS      add ECFLAGS to CFLAGS [$CFLAGS]
@@ -1296,7 +1296,7 @@ process_detect() {
 }
 
 enable logging
-logfile="config.err"
+logfile="config.log"
 self=$0
 process() {
     cmdline_args="$@"