kits/package: Break LibsolvSolver add-on out

* BSolver is implemented by solver add-ons
* We may want to (unlikely) leverage another
  package solver in the future.
* We may want to (likely) implement a dummy
  solver when libsolv is unavailable on new
  architectures without bootstrap.
* This also makes solving missing libsolv a little
  more graceful vs the "include "libsolv.h" not
  found.

Change-Id: Iedd9d0f022fb743c4c7606bd33a4b6dbef0576f7
Reviewed-on: https://review.haiku-os.org/c/haiku/+/819
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

src/build/libpackage/solver/Jamfile

@@ -10,7 +10,7 @@ UsePrivateHeaders shared ;
 USES_BE_API on libpackage-add-on-libsolv_build.so = true ;
 
 SEARCH_SOURCE += [ FDirName $(HAIKU_TOP) src kits package solver ] ;
-
+SEARCH_SOURCE += [ FDirName $(HAIKU_TOP) src kits package solver libsolv ] ;
 
 MakeLocate libpackage-add-on-libsolv_build.so
 	: $(HOST_BUILD_COMPATIBILITY_LIB_DIR) ;
@@ -24,6 +24,5 @@ BuildPlatformSharedLibrary libpackage-add-on-libsolv_build.so
 	libbe_build.so $(HOST_LIBSTDC++)
 ;
 
-
 Includes [ FGristFiles LibsolvSolver.cpp ]
 	: [ BuildFeatureAttribute libsolv : headers ] ;

src/kits/package/Jamfile

@@ -71,10 +71,6 @@ for architectureObject in [ MultiArchSubDirSetup ] {
 		SEARCH_SOURCE += [ FDirName $(HAIKU_TOP) src kits package manager ] ;
 		SEARCH_SOURCE += [ FDirName $(HAIKU_TOP) src kits package solver ] ;
 
-		AddResources $(libsolv) :
-			LibsolvSolver.rdef
-			;
-
 		SharedLibrary [ MultiArchDefaultGristFiles libpackage.so ]
 			:
 			ActivateRepositoryCacheJob.cpp

src/kits/package/solver/Jamfile

@@ -1,41 +1,10 @@
 SubDir HAIKU_TOP src kits package solver ;
 
-# add-on implementing a libsolv based BSolver
-
-local architectureObject ;
-for architectureObject in [ MultiArchSubDirSetup ] {
-	on $(architectureObject) {
-
-		UseBuildFeatureHeaders libsolv ;
-
-		local libsolvHeaders
-			= [ BuildFeatureAttribute libsolv : headers : path ] ;
-		UseHeaders [ FDirName $(libsolvHeaders) solv ] ;
-
-		AddResources $(libsolv) :
-			LibsolvSolver.rdef
-			;
-
-		UsePrivateHeaders shared ;
-
-		SharedLibrary
-			[ MultiArchDefaultGristFiles libpackage-add-on-libsolv.so ]
-			:
-			LibsolvSolver.cpp
-			:
-			package
-			[ BuildFeatureAttribute libsolv : libraries ]
-			be [ TargetLibstdc++ ]
-		;
-
-		Includes [ FGristFiles LibsolvSolver.cpp ]
-			: [ BuildFeatureAttribute libsolv : headers ] ;
-	}
-}
-
 DoCatalogs libsolv :
 	x-vnd.Haiku-libsolvsolver
 	:
 	SolverProblem.cpp
 	SolverProblemSolution.cpp
 ;
+
+HaikuSubInclude libsolv ;

src/kits/package/solver/libsolv/Jamfile

@@ -0,0 +1,34 @@
+SubDir HAIKU_TOP src kits package solver libsolv ;
+
+# add-on implementing a libsolv based BSolver
+
+local architectureObject ;
+for architectureObject in [ MultiArchSubDirSetup ] {
+	on $(architectureObject) {
+
+		UseBuildFeatureHeaders libsolv ;
+
+		local libsolvHeaders
+			= [ BuildFeatureAttribute libsolv : headers : path ] ;
+		UseHeaders [ FDirName $(libsolvHeaders) solv ] ;
+
+		AddResources $(libsolv) :
+			LibsolvSolver.rdef
+			;
+
+		UsePrivateHeaders shared ;
+
+		SharedLibrary
+			[ MultiArchDefaultGristFiles libpackage-add-on-libsolv.so ]
+			:
+			LibsolvSolver.cpp
+			:
+			package
+			[ BuildFeatureAttribute libsolv : libraries ]
+			be [ TargetLibstdc++ ]
+		;
+
+		Includes [ FGristFiles LibsolvSolver.cpp ]
+			: [ BuildFeatureAttribute libsolv : headers ] ;
+	}
+}