[testsuite, committed] Fix think-o in calls to gdb_compile

[Sandra Loosemore <sandra at codesourcery dot com>]

In cross-testing on an arm-none-linux-gnueabi toolchain, I found that 
the test programs for gdb.base/nested-subp*.exp were being built without 
the appropriate command-line options for an executable, which was 
causing them to be un-runnable on the remote target.  There's nothing 
ARM-specific here -- the trouble turned out to be a think-o in the calls 
to gdb_compile.  It wants the literal token "executable" for the 
argument corresponding to the "type" parameter, not the name of the 
executable.  I think this is a sufficiently obvious fix that I've gone 
ahead and committed it.

-Sandra

2015-11-19  Sandra Loosemore  <sandra@codesourcery.com>

	gdb/testsuite/
	* gdb.base/nested-subp1.exp: Pass executable, not executable name,
	as type argument to gdb_compile.
	* gdb.base/nested-subp2.exp: Likewise.
	* gdb.base/nested-subp3.exp: Likewise.

diff --git a/gdb/testsuite/gdb.base/nested-subp1.exp b/gdb/testsuite/gdb.base/nested-subp1.exp
index 9720f5b..adfcad3 100644
--- a/gdb/testsuite/gdb.base/nested-subp1.exp
+++ b/gdb/testsuite/gdb.base/nested-subp1.exp
@@ -26,7 +26,7 @@ set testcase "nested-subp1"
 
 if { [gdb_compile "${srcdir}/${subdir}/${testcase}.c" \
                   [standard_output_file "${testcase}"] \
-                  "${testcase}" \
+                  executable \
                   [list debug "additional_flags=-std=gnu99"]] != "" } {
     return -1
 }
diff --git a/gdb/testsuite/gdb.base/nested-subp2.exp b/gdb/testsuite/gdb.base/nested-subp2.exp
index a107d1c..d4fb6f1 100644
--- a/gdb/testsuite/gdb.base/nested-subp2.exp
+++ b/gdb/testsuite/gdb.base/nested-subp2.exp
@@ -26,7 +26,7 @@ set testcase "nested-subp2"
 
 if { [gdb_compile "${srcdir}/${subdir}/${testcase}.c" \
                   [standard_output_file "${testcase}"] \
-                  "${testcase}" \
+                  executable \
                   [list debug "additional_flags=-std=gnu99"]] != "" } {
     return -1
 }
diff --git a/gdb/testsuite/gdb.base/nested-subp3.exp b/gdb/testsuite/gdb.base/nested-subp3.exp
index 8f9b522..0cb10f1 100644
--- a/gdb/testsuite/gdb.base/nested-subp3.exp
+++ b/gdb/testsuite/gdb.base/nested-subp3.exp
@@ -26,7 +26,7 @@ set testcase "nested-subp3"
 
 if { [gdb_compile "${srcdir}/${subdir}/${testcase}.c" \
                   [standard_output_file "${testcase}"] \
-                  "${testcase}" \
+                  executable \
                   [list debug "additional_flags=-std=gnu99"]] != "" } {
     return -1
 }