[PATCH] configure: Add flags for MinGW32 standalone build

[Joshua Watt <jpewhacker@gmail.com>]

There are two cases that need to be accounted for when compiling QEMU
for MinGW32:
 1) A standalone distribution, where QEMU is self contained and
    extracted by the user, such as a user would download from the QEMU
    website. In this case, all of the QEMU files should be rooted in
    $prefix to ensure they can be easily packaged together for
    distribution
 2) QEMU integrated into a distribution image/sysroot/SDK and
    distributed with other programs. In this case, the provided
    arguments for bindir/datadir/etc. should be respected as they for a
    Linux build.

Add a configure time flags --enable-standalone-mingw and
--disable-standalone-mingw that allows the user to control this
behavior. The flag defaults to "enabled" if unspecified to retain the
existing build behavior

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
---
 configure | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index 5860bdb77b..5c83edb502 100755
--- a/configure
+++ b/configure
@@ -358,6 +358,7 @@ strip_opt="yes"
 tcg_interpreter="no"
 bigendian="no"
 mingw32="no"
+mingw32_standalone="yes"
 gcov="no"
 EXESUF="$default_feature"
 HOST_DSOSUF=".so"
@@ -1558,6 +1559,10 @@ for opt do
   ;;
   --disable-fuse-lseek) fuse_lseek="disabled"
   ;;
+  --enable-standalone-mingw) mingw32_standalone="yes"
+  ;;
+  --disable-standalone-mingw) mingw32_standalone="no"
+  ;;
   *)
       echo "ERROR: unknown option $opt"
       echo "Try '$0 --help' for more information"
@@ -1570,7 +1575,7 @@ libdir="${libdir:-$prefix/lib}"
 libexecdir="${libexecdir:-$prefix/libexec}"
 includedir="${includedir:-$prefix/include}"
 
-if test "$mingw32" = "yes" ; then
+if test "$mingw32" = "yes" && test "$mingw32_standalone" = "yes"; then
     mandir="$prefix"
     datadir="$prefix"
     docdir="$prefix"
@@ -1897,6 +1902,7 @@ disabled with --disable-FEATURE, default is enabled if available
   libdaxctl       libdaxctl support
   fuse            FUSE block device export
   fuse-lseek      SEEK_HOLE/SEEK_DATA support for FUSE exports
+  standalone-mingw  Build for standalone distribution on MinGW
 
 NOTE: The object files are built at the place where configure is launched
 EOF
-- 
2.30.0